CVE-2011-1156

feedparser denial of service vulnerability

5.0 MediumFix available

feedparser.py in Universal Feed Parser (aka feedparser or python-feedparser) before 5.0.1 allows remote attackers to cause a denial of service (application crash) via a malformed DOCTYPE declaration.

Exploit likelihood

3.26%Up 1.1 points since Feb 4, 2022

What each source reports

NVD Score used5.0

feedparser.py in Universal Feed Parser (aka feedparser or python-feedparser) before 5.0.1 allows remote attackers to cause a denial of service (application crash) via a malformed DOCTYPE declaration.

Record: CVE-2011-1156
CVSS 2.0: 5.0 MediumAV:N/AC:L/Au:N/C:N/I:N/A:P
Weakness: CWE-399
Updated: 2026-11-02

CVE ListNo score

feedparser.py in Universal Feed Parser (aka feedparser or python-feedparser) before 5.0.1 allows remote attackers to cause a denial of service (application crash) via a malformed DOCTYPE declaration.

Record: CVE-2011-1156
Updated: 2026-11-02

EUVDEUVD-2011-0014No score

feedparser.py in Universal Feed Parser (aka feedparser or python-feedparser) before 5.0.1 allows remote attackers to cause a denial of service (application crash) via a malformed DOCTYPE declaration.

Record: EUVD-2011-0014
Updated: 2026-11-03

GitHub AdvisoriesGHSA-6h52-4vmh-8x4f8.7

feedparser denial of service vulnerability

feedparser.py in Universal Feed Parser (aka feedparser or python-feedparser) before 5.0.1 allows remote attackers to cause a denial of service (application crash) via a malformed DOCTYPE declaration.

Record: GHSA-6h52-4vmh-8x4f
CVSS 4.0: 8.7 HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness: CWE-20
Updated: 2026-11-02

OSVGHSA-6h52-4vmh-8x4f8.7

feedparser denial of service vulnerability

feedparser.py in Universal Feed Parser (aka feedparser or python-feedparser) before 5.0.1 allows remote attackers to cause a denial of service (application crash) via a malformed DOCTYPE declaration.

Record: GHSA-6h52-4vmh-8x4f
CVSS 4.0: 8.7 HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness: CWE-20
Updated: 2026-11-02

OSVNo score

feedparser.py in Universal Feed Parser (aka feedparser or python-feedparser) before 5.0.1 allows remote attackers to cause a denial of service (application crash) via a malformed DOCTYPE declaration.

Record: CVE-2011-1156
Updated: 2026-11-02

OSVDEBIAN-CVE-2011-1156No score

feedparser.py in Universal Feed Parser (aka feedparser or python-feedparser) before 5.0.1 allows remote attackers to cause a denial of service (application crash) via a malformed DOCTYPE declaration.

Record: DEBIAN-CVE-2011-1156
Updated: 2026-11-02

OSVPYSEC-2011-19No score

feedparser.py in Universal Feed Parser (aka feedparser or python-feedparser) before 5.0.1 allows remote attackers to cause a denial of service (application crash) via a malformed DOCTYPE declaration.

Record: PYSEC-2011-19
Updated: 2026-11-02

Affected products

mark pilgrim feedparser

Affected packages

Affected packages
Package	Affected	Fixed
`feedparser` PyPI	4.1 up to 5.0.1	5.0.1
`feedparser` Debian:12	before 5.0.1-1	5.0.1-1
`feedparser` Debian:13	before 5.0.1-1	5.0.1-1
`feedparser` Debian:14	before 5.0.1-1	5.0.1-1
`feedparser` PyPI	4.1 up to 5.0.1, plus listed versions 5.0	5.0.1
`feedparser` PyPI	before 5.0.1, plus listed versions 4.15.0	5.0.1

History

History
Recorded	Changed	Sources
Nov 10, 2026	facts
Nov 3, 2026	aliases	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2011-1156 is a medium vulnerability (CVSS 5.0) in Mark Pilgrim Feedparser, published April 11, 2011. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 3.26%, the 88th percentile. Fixed in feedparser 5.0.1.

References

Show 11 moreShow less