| Name | CVE-2026-18503 |
| Description | Attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU when applications pass unbounded input to csv.Sniffer.sniff(). |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| pypy3 (PTS) | bookworm | 7.3.11+dfsg-2+deb12u3 | vulnerable |
| trixie | 7.3.19+dfsg-2 | vulnerable | |
| forky, sid | 7.3.23+dfsg-1 | vulnerable | |
| python3.11 (PTS) | bookworm | 3.11.2-6+deb12u8 | vulnerable |
| bookworm (security) | 3.11.2-6+deb12u3 | vulnerable | |
| python3.13 (PTS) | trixie | 3.13.5-2+deb13u3 | vulnerable |
| forky, sid | 3.13.15-1 | fixed | |
| python3.14 (PTS) | forky, sid | 3.14.7-1 | fixed |
| python3.15 (PTS) | forky | 3.15.0~rc1-1 | fixed |
| sid | 3.15.0~rc2-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| pypy3 | source | (unstable) | (unfixed) | |||
| python2.7 | source | bullseye | (unfixed) | end-of-life | ||
| python2.7 | source | (unstable) | (unfixed) | |||
| python3.11 | source | (unstable) | (unfixed) | |||
| python3.13 | source | (unstable) | 3.13.15-1 | |||
| python3.14 | source | (unstable) | 3.14.7-1 | |||
| python3.15 | source | (unstable) | 3.15.0~rc1-1 | |||
| python3.9 | source | (unstable) | (unfixed) |
[trixie] - python3.13 <no-dsa> (Minor issue)
[bullseye] - python2.7 <end-of-life> (EOL in bullseye LTS)
[trixie] - pypy3 <no-dsa> (Minor issue)
https://mail.python.org/archives/list/security-announce@python.org/thread/KQ7NBMCPAZJHRROQXJQE4GMXGLD5KHBS/
https://github.com/python/cpython/issues/98820
https://github.com/python/cpython/pull/153694
Fixed by: https://github.com/python/cpython/commit/476fb09cdb0d73e645849d98c610e7e5697ce7c9 (v3.15.0rc1)
Fixed by: https://github.com/python/cpython/commit/89f29c760c02774b099ddd6863268eb13fa3946a (v3.14.7)
Fixed by: https://github.com/python/cpython/commit/b30c7fa9edd921a118f286e9f90f560777fa693b (v3.13.15)
Fixed by: https://github.com/python/cpython/commit/063d4555c94ef412c731527dbf30193327f2ee82 (v3.12.14)
Fixed by: https://github.com/python/cpython/commit/b09a67a20c464f8288c9f9a6b9c7082a74560024 (v3.11.16)
Fixed by: https://github.com/python/cpython/commit/fd78b565d7c326f96ae903ab945b47f35d829cf4 (v3.10.21)