CVE catalog
CVE-2026-91992
Tornado before 6.5.7 contains a credential leak vulnerability in CurlAsyncHTTPClient where pycurl handles are reused across requests without proper state clearing. Attackers can obtain sensitive crede
- Severity
- Critical · CVSS 9
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:L/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Published
- Updated
- Source
- [NVD] · [CVE record]
- EPSS
- 0.24% · Oct 25, 2026
Tornado before 6.5.7 contains a credential leak vulnerability in CurlAsyncHTTPClient where pycurl handles are reused across requests without proper state clearing. Attackers can obtain sensitive credentials by issuing requests through the same client instance, allowing TLS certificates or proxy authentication to persist across unintended requests.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | python-tornado | sid | 6.5.5-5 | vulnerable |
| Debian | python-tornado | forky | 6.5.5-5 | vulnerable |
| Debian | python-tornado | trixie | 6.4.2-3+deb13u2 | vulnerable |
| Debian | python-tornado | trixie-security | 6.4.2-3+deb13u2 | vulnerable |
| Debian | python-tornado | bookworm | 6.2.0-3+deb12u4 | vulnerable |
| Debian | python-tornado | bookworm-security | 6.2.0-3+deb12u4 | vulnerable |
| Ubuntu | python-tornado | noble | 6.4.0-1ubuntu0.6 | fixed |
| Ubuntu | python-tornado-doc | noble | 6.4.0-1ubuntu0.6 | fixed |
| Ubuntu | python3-tornado | noble | 6.4.0-1ubuntu0.6 | fixed |
| Ubuntu | python-tornado | pro | 6.1.0-1build1 | vulnerable |
| Ubuntu | python-tornado | pro | 6.1.0-2 | vulnerable |
| Ubuntu | python-tornado | pro | 6.1.0-3 | vulnerable |
| Ubuntu | python-tornado | pro | 6.1.0-3build1 | vulnerable |
| Ubuntu | python-tornado | pro | 6.1.0-3ubuntu0.1~esm1 | vulnerable |
| Ubuntu | python-tornado | pro | 6.1.0-3ubuntu0.1~esm2 | vulnerable |
| Ubuntu | python-tornado | pro | 6.1.0-3ubuntu0.1~esm4 | vulnerable |
| Ubuntu | python-tornado | pro | 6.1.0-3ubuntu0.1~esm5 | vulnerable |
| Ubuntu | python-tornado | pro | 6.1.0-3ubuntu0.1~esm6 | fixed |
| Ubuntu | python-tornado | 24.04 | 6.3.2-1 | vulnerable |
| Ubuntu | python-tornado | 24.04 | 6.4.0-0ubuntu1 | vulnerable |
| Ubuntu | python-tornado | 24.04 | 6.4.0-1 | vulnerable |
| Ubuntu | python-tornado | 24.04 | 6.4.0-1build1 | vulnerable |
| Ubuntu | python-tornado | 24.04 | 6.4.0-1ubuntu0.1 | vulnerable |
| Ubuntu | python-tornado | 24.04 | 6.4.0-1ubuntu0.2 | vulnerable |
| Ubuntu | python-tornado | 24.04 | 6.4.0-1ubuntu0.4 | vulnerable |
| Ubuntu | python-tornado | 24.04 | 6.4.0-1ubuntu0.5 | vulnerable |
| Ubuntu | python-tornado | 24.04 | 6.4.0-1ubuntu0.6 | fixed |
| Ubuntu | python-tornado | 26.04 | 6.4.2-3 | vulnerable |
| Ubuntu | python-tornado | 26.04 | 6.5.2-3 | vulnerable |
| Ubuntu | python-tornado | 26.04 | 6.5.4-0.1 | vulnerable |
| Ubuntu | python-tornado | 26.04 | 6.5.4-0.1ubuntu0.1 | vulnerable |
| Ubuntu | python-tornado | 26.04 | 6.5.4-0.1ubuntu0.2 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | python-tornado | source | sid | (unfixed) | not yet assigned | Not reported | [1148323] |
| Debian | python-tornado | source | forky | (unfixed) | not yet assigned | Not reported | [1148323] |
| Debian | python-tornado | source | trixie | (unfixed) | not yet assigned | Not reported | [1148323] |
| Debian | python-tornado | source | bookworm | (unfixed) | not yet assigned | Not reported | [1148323] |
| Ubuntu | python-tornado | deb | noble | 6.4.0-1ubuntu0.6 | Not reported | Not reported | Not reported |
| Ubuntu | python-tornado-doc | deb | noble | 6.4.0-1ubuntu0.6 | Not reported | Not reported | Not reported |
| Ubuntu | python3-tornado | deb | noble | 6.4.0-1ubuntu0.6 | Not reported | Not reported | Not reported |
| Ubuntu | python-tornado | deb | pro | 6.1.0-3ubuntu0.1~esm6 | Not reported | UBUNTU-CVE-2026-91992 | Not reported |
| Ubuntu | python-tornado | deb | 24.04 | 6.4.0-1ubuntu0.6 | Not reported | UBUNTU-CVE-2026-91992 | Not reported |
| Ubuntu | python-tornado | deb | 26.04 | 6.5.4-0.1ubuntu0.2 | Not reported | UBUNTU-CVE-2026-91992 | Not reported |
Notes
[trixie] python-tornado: Minor issue
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [python3-tornado]Affected
Source package: [python-tornado]
Details (4)
6.2.0-3+deb12u4· amd64 · bookwormAffected
nvd · python-tornado · debian · bookworm; nvd · python-tornado · debian · 12
6.2.0-3+deb12u4· arm64 · bookwormAffected
nvd · python-tornado · debian · bookworm; nvd · python-tornado · debian · 12
6.2.0-3+deb12u4· amd64 · bookworm-securityAffected
nvd · python-tornado · debian · bookworm; nvd · python-tornado · debian · 12
6.2.0-3+deb12u4· arm64 · bookworm-securityAffected
nvd · python-tornado · debian · bookworm; nvd · python-tornado · debian · 12
- [python-tornado-doc]Affected
Source package: [python-tornado]
Details (4)
6.2.0-3+deb12u4· all · bookwormAffected
nvd · python-tornado · debian · bookworm; nvd · python-tornado · debian · 12
6.2.0-3+deb12u4· all · bookwormAffected
nvd · python-tornado · debian · bookworm; nvd · python-tornado · debian · 12
6.2.0-3+deb12u4· all · bookworm-securityAffected
nvd · python-tornado · debian · bookworm; nvd · python-tornado · debian · 12
6.2.0-3+deb12u4· all · bookworm-securityAffected
nvd · python-tornado · debian · bookworm; nvd · python-tornado · debian · 12
[Debian 13 (Trixie)]
- [python3-tornado]Affected
Source package: [python-tornado]
Details (4)
6.4.2-3+deb13u2· amd64 · trixieAffected
nvd · python-tornado · debian · 13
6.4.2-3+deb13u2· arm64 · trixieAffected
nvd · python-tornado · debian · 13
6.4.2-3+deb13u2· amd64 · trixie-securityAffected
nvd · python-tornado · debian · 13
6.4.2-3+deb13u2· arm64 · trixie-securityAffected
nvd · python-tornado · debian · 13
- [python-tornado-doc]Affected
Source package: [python-tornado]
Details (4)
6.4.2-3+deb13u2· all · trixieAffected
nvd · python-tornado · debian · 13
6.4.2-3+deb13u2· all · trixieAffected
nvd · python-tornado · debian · 13
6.4.2-3+deb13u2· all · trixie-securityAffected
nvd · python-tornado · debian · 13
6.4.2-3+deb13u2· all · trixie-securityAffected
nvd · python-tornado · debian · 13
Observed:
References
- [https://nvd.nist.gov/vuln/detail/CVE-2026-91992]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-91992]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2026-91992]
- [https://security-tracker.debian.org/tracker/CVE-2026-91992]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91992.json]
- [https://ubuntu.com/security/notices/USN-8952-1]
[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [Ubuntu Security Notices (USN)]