| Name | CVE-2026-6019 |
| Description | http.cookies.Morsel.js_output() returns an inline <script> snippet and only escapes " for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence </script> inside the generated script element. Mitigation base64-encodes the cookie value to disallow escaping using cookie value. |
| 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) |
| Debian Bugs | 1135116 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| pypy3 (PTS) | bullseye | 7.3.5+dfsg-2+deb11u2 | vulnerable |
| bullseye (security) | 7.3.5+dfsg-2+deb11u5 | vulnerable | |
| bookworm | 7.3.11+dfsg-2+deb12u3 | vulnerable | |
| trixie | 7.3.19+dfsg-2 | vulnerable | |
| forky, sid | 7.3.22+dfsg-1 | vulnerable | |
| python3.11 (PTS) | bookworm | 3.11.2-6+deb12u6 | vulnerable |
| bookworm (security) | 3.11.2-6+deb12u3 | vulnerable | |
| python3.13 (PTS) | trixie | 3.13.5-2 | vulnerable |
| forky, sid | 3.13.12-1 | vulnerable | |
| python3.14 (PTS) | forky | 3.14.4-2 | vulnerable |
| sid | 3.14.5~rc1-1 | fixed | |
| python3.9 (PTS) | bullseye | 3.9.2-1 | vulnerable |
| bullseye (security) | 3.9.2-1+deb11u6 | vulnerable |
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) | 1135116 | ||
| python3.11 | source | (unstable) | (unfixed) | |||
| python3.13 | source | (unstable) | (unfixed) | |||
| python3.14 | source | (unstable) | 3.14.5~rc1-1 | |||
| python3.9 | source | (unstable) | (unfixed) |
[trixie] - python3.13 <no-dsa> (Minor issue)
[bookworm] - python3.11 <no-dsa> (Minor issue)
[trixie] - pypy3 <no-dsa> (Minor issue)
[bookworm] - pypy3 <no-dsa> (Minor issue)
[bullseye] - pypy3 <postponed> (Minor issue; can be fixed in next update)
https://mail.python.org/archives/list/security-announce@python.org/thread/IVNWGV2BBNC3RHQAFS22UP4DY56SAXX3/
https://github.com/python/cpython/issues/90309
https://github.com/python/cpython/pull/148848
Fixed by: https://github.com/python/cpython/commit/76b3923d688c0efc580658476c5f525ec8735104 (main branch)
Fixed by: https://github.com/python/cpython/commit/f795e042043dfe26c42e1971d4502c1cdc4c65b8 (v3.14.5rc1)
Fixed by: https://github.com/python/cpython/commit/3c59b8b53fc75c7f9578d16fb8201ceb43e8f76c (3.13 branch)