The tutorial is where most people meet jq, but it was missing key
filters like select and abbreviated commands in ways that are hard for
beginners to follow.
Grow the page from 7 examples to 24, newly covering -r and -c, chained
paths and slicing, map, sort_by, group_by, select, test, to_entries,
from_entries, with_entries, string interpolation and @tsv. The sample
data is pinned with the API's until parameter and the outputs avoid
GitHub account data, so running the commands gives exactly the output
shown.
A call passing more than 4095 arguments at the start of a nested
function body aborted jq after reporting the compile errors, with
"Assertion failed: (nemb > 0 && sz > 0), function jv_mem_calloc" and
exit status 134.
Stop compiling a function before its bytecode is allocated when it has
compile errors, since the bytecode is only generated and used when
compilation succeeds. jq now prints the same compile errors followed by
"jq: 2 compile errors" and exits with status 3, as it does for other
compile errors, instead of crashing.
The UTF-8 BOM was stripped only at the start of the parser stream, but jq
feeds all input files into a single parser, so a BOM at the start of the
second and later files reached the parser as content and failed with a
confusing "Invalid numeric literal" error. Strip it in the file readers
instead, at the start of each input file including stdin, and in
jv_load_file.
This also strips the BOM for raw input, so -R and --rawfile no longer
yield a leading U+FEFF, and a BOM at the start of a -f program file or an
imported module is now accepted rather than reported as a syntax error.
In exchange, "\uFEFF1" | fromjson is now a parse error, since a U+FEFF
inside a string is content rather than an encoding marker, and the
dedicated "Malformed BOM" error is gone.
The date in the .TH line of jq.1.prebuilt changed whenever the manual was
regenerated in a new month, causing merge conflicts between pull requests
that touch the manual, and it did not reflect the release date anyway.
Generate the committed man page without a date.
Stamp the date into jq.1 at build time instead, taking it from the current
commit, or from SOURCE_DATE_EPOCH where that is set, so that release
tarballs and distribution builds still carry one and the behaviour added
in #3514 is kept. Write it in UTC and in ISO 8601 rather than the previous
"%B %Y", for which mandoc reports "cannot parse date, using it verbatim".
`fromdateiso8601` was `strptime("%Y-%m-%dT%H:%M:%SZ") | mktime`, which
accepts only one of the many representations ISO 8601 permits. strptime
cannot be extended to cover the rest portably, since it has no specifier
for fractional seconds and glibc discards `%G` and `%V`.
Replace it with a parser in src/iso8601.c that handles basic and extended
representations, ordinal and week dates, fractional seconds, offsets and
date-only input. It uses integer arithmetic instead of `time_t`, so the
results no longer depend on the platform.
This is stricter than before. Impossible dates like `2015-02-30`, which
`mktime` used to normalize into March, and unpadded components like
`2015-3-5T6:00:00Z` are now errors. So is any trailing input, including
whitespace. Leading whitespace is rejected too; before, glibc skipped it
and macOS did not. A leap second now maps to the second before it rather
than the next minute. The error message has changed, and the result can
now be non-integer.
The push trigger had no branch filter, so pull requests from branches
in this repository (e.g. Dependabot) ran the workflow twice, once for
push and once for pull_request.
`reduce f as $x (init; update)` evaluated `f` against a stack slot
that forkpoints created while evaluating `init` restore. Both the
`DUPN` opening the reduction loop and the `LOADVN` retrieving the
result pop that slot destructively, nulling it out, so an `init`
that backtracks (e.g. `0, 0`) made `f` see `null` and fail with
"Cannot iterate over null".
Duplicate the input before the `FORK` instead of inside the loop,
and drop the leftover copy with `POP` once the loop is exhausted.
The slot left live at the `FORK` is then a block pushed after
`init` completed, which no earlier forkpoint can reach, so nulling
it is harmless. This is the same approach `gen_foreach` has used
since c70ae1a.
`DUPN` had no other user, so remove the opcode.
block_mark_referenced walks the joined block backwards and skips the
body of any definition not yet marked referenced, so a library must
precede its importers. f58787c41 registered a library before walking
its dependencies, to have somewhere to keep the `loading` flag, which
reversed that order and made block_drop_unreferenced free definitions
that are still referenced through bound_by.
Keep the libraries being loaded on a stack threaded through the
load_library frames instead, so registration can move back after the
dependency walk.
The whole seconds were truncated toward zero while the fractional part
was measured from the floor, so any negative non-integral timestamp was
rendered one second late; gmtime was not monotonic across the epoch.
Only the latest release stays visible in the binary, checksum and
signature, and source tarball lists; older versions move into
collapsible `<details>` sections. Condense the repetitive per-version
checksum and signature sentences into a single list.
The bundle generated by actions/attest is currently only retrievable
via the GitHub attestations API, which requires authentication.
Uploading it as jq-attestation.json lets downstream consumers
(distro packagers, unauthenticated CI) verify provenance offline.
The bound added in CVE-2026-32316 (e47e56d22) still allowed
`sizeof(jvp_string) + (currlen + len) * 2 + 1` to wrap `size_t` on
32-bit platforms. Tighten the threshold so the final allocation
fits in 32-bit `size_t`.
Also break out of `jv_string_implode` and `f_string_implode` once
`jv_string_append_codepoint` returns an invalid `jv`; otherwise the
next iteration triggers the assertion in `jvp_string_ptr` (or
invokes undefined behavior under `-DNDEBUG`).
Fixes CVE-2026-54679.
Co-authored-by: Dirk Müller <dirk@dmllr.de>
When `jv_string_append_buf` overflows the string length limit,
it returns an invalid `jv`; `jv_load_file` then re-entered it
on the invalid value and overran the heap. Break out of the loop
once the value is invalid.
Fixes CVE-2026-49839.
The table was declared with 255 entries but indexed by an unsigned
char, so the decoder would read one byte past the array for input
bytes equal to 0xFF. Through jq's normal input paths the over-read
is unreachable because invalid UTF-8 bytes are normalized to U+FFFD
before reaching @base64d, but the table is still wrong at the C
level and reachable by libjq callers that construct strings via
the C API without UTF-8 validation.
jq used to recurse without bound on mutual or self-referential
`import` declarations, exhausting the stack. Track each library's
load state with a `loading` flag set before its dependencies are
processed; a recursive reference to an in-progress library now
reports "circular import of X".
Fixes CVE-2026-44777.
jq accepts embedded NUL bytes at the language level but resolves
module import paths through NUL-terminated C strings, so the path
validated by policy or audit code could differ from the on-disk
path jq actually opens. Pass jv through gen_import so the AST
preserves the original bytes, and reject embedded NULs in
validate_relpath.
Fixes CVE-2026-43895.
A signed-int overflow in decNumber's D2U macro lets huge literals
write attacker-controlled bytes past a stack buffer. Cap the length
before calling decNumberFromString, and pre-slice long strings in
jv_dump_string_trunc so the resulting error message doesn't itself
allocate a multi-GiB buffer.
Fixes CVE-2026-43894.
Deeply nested path arrays can cause unbounded recursion in
`jv_setpath`, `jv_getpath`, and `jv_delpaths`, leading to
stack overflow. Add a depth limit of 10000 to match the
existing `tojson` depth limit. This fixes CVE-2026-33947.
The hash function used a fixed seed, allowing attackers to craft colliding keys
and cause O(n^2) object parsing performance. Initialize the seed from a random
source at process startup to prevent the attack. This fixes CVE-2026-40164.
Co-authored-by: Asaf Meizner <asafmeizner@gmail.com>
In `jvp_string_append`, the allocation size `(currlen + len) * 2` could
overflow `uint32_t` when `currlen + len` exceeds `INT_MAX`, causing a small
allocation followed by a large `memcpy`.
In `jvp_string_copy_replace_bad`, the output buffer size calculation
`length * 3 + 1` could overflow `uint32_t`, again resulting in a small
allocation followed by a large write.
Add overflow checks to both functions to return an error for strings
that would exceed `INT_MAX` in length. Fixes CVE-2026-32316.
- Fix segfault when --skip/--take is the last argument.
- Fix FILE handle leak: opened test files were never closed.
- Support running multiple test files in one invocation.
When a module fails to parse as a library, `load_library` cached the
invalid block. A second import/include of the same module would find
the cached invalid block and pass it to `block_bind_library`,
triggering the assertion failure. Skip caching the block when there
are parse errors to avoid this problem.
This commit improves performance by refactoring `@uri` and `@urid`
to pre-alloacte buffers and build the `jv` string at the end.
Also, this fixes `@urid` to prevent multi-byte UTF-8 corruption,
and to preserve embedded null bytes.
The `jv_string_empty` did not properly null-terminate the string data,
which could lead to a heap buffer overflow. The test case of
GHSA-p7rr-28xf-3m5w (`0[""*0]`) was fixed by the commit dc849e9bb7,
but another case (`0[[]|implode]`) was still vulnerable. This commit
ensures string data is properly null-terminated, and fixes CVE-2025-48060.
Previously, the precedence of `as` binding was higher than the binary
operators. This results in unexpected behaviors, `1 + 2 as $x | -$x`
was `-1` instead of `-3`. The commit 92daac90f6 (PR #3053) changed
the behavior to emit syntax error on this case. Now, this commit allows
binary operators with `as` binding. This fixes#2446, and fixes#3284.
This commit fixes signed integer overflow and SEGV issues on growing
arrays and objects. The size of arrays and objects is now limited to
`536870912` (`0x20000000`). This fixes CVE-2024-23337 and fixes#3262.
This commit improves the parser and compiler error messages, making
it more easier to understand where in the filter the problem is.
Like modern compilers, jq will show the line in the filter where the
error occurred, will display squiggly line under the invalid token.
This commit improves the parser to fix some unintuitive results of the unary
operator `-` (e.g. `[-1 as $x | 1,$x]` is now `[1,-1]`, previously `[-1,-1]`).
Also, this commit now allows to use binary operator expressions, `reduce`,
`foreach`, `if`, and `try` expressions for object values.
This commit refactors `splits/2` implementation using `foreach` syntax
and reduces intermediate arrays. This refactoring removes an unnecessary
private (and undocumented) filter `_nwise` and closes#3148.
This commit drops support for parsing NaN with payload in JSON like
`NaN123` and fixes CVE-2024-53427. Other JSON extensions like `NaN` and
`Infinity` are still supported. Fixes#3023, fixes#3196, fixes#3246.
Using `calloc` function with a count of zero elements is implementation
defined and it may cause allocation errors on some platforms (ref #3277).
This commit fixes `jv_mem_calloc` callers to avoid undefined behavior.
When we use a large format string to `strftime/1` and `strflocaltime/1`,
we get segmentation fault. This happens because the result buffer is
allocated on the stack using `alloca` function, and `strftime` function
writes out of the space when the size is not enough to format time.
I fixed the segmentation fault issue by allocating the result buffer on
the heap using `malloc` function, because `alloca` function does not
provide a way to detect insufficient space.
This commit improves the performance of repeating strings, by copying
the result string instead of the string being repeated. Also it adds
an error message when the result string is too long.
Previously, the configure script automatically enables Valgrind during
testing when the valgrind command is found. However, running tests with
Valgrind is quite slow, so it is better to disable it by default, and
to enable it only when the user specifies the `--enable-valgrind` flag.
On OpenBSD, some prototypes are hidden behind `_BSD_SOURCE`.
Defining this variable fixes#3252, and also fixes#3276.
This can be seen as a regression of #2631.
Previously, `unique` and `unique_by` filters are implemented using
`group_by` and then `map(.[0])`. This commit re-implements in C, to
avoid unnecessary boxing of grouping, and improves the performance.
Whether `char` has a sign is implementation dependent, and `c >= 0` may
result in a compiler warning. We can use bitwise operator to check
whether the character is a control character, regardless of the sign.
The code of `jv_number_value` is intended to cache the double value of
literal numbers, but it does not work because it accepts the `jv` struct
by value. This patch fixes the behavior by checking if the double value
is `NaN`, which indicates the unconverted value. This patch improves the
performance of major use cases; e.g. `range(1000000)` runs 25% faster.
We no longer use the `--root` option of `build_website.py` since we have
moved to jqlang.org (from jqlang.github.io/jq where the root was `/jq`).
We don't need the option on local development either since `http.server`
has the `-d` option to specify the directory to serve from.
itchyny