CVE-2025-8194
published 2025-07-28CVE-2025-8194: There is a defect in the CPython “tarfile” module affecting the “TarFile” extraction and entry enumeration APIs. The tar implementation would process tar…
PriorityP340high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.61%
45.3th percentile
There is a defect in the CPython “tarfile” module affecting the “TarFile” extraction and entry enumeration APIs. The tar implementation would process tar archives with negative offsets without error, resulting in an infinite loop and deadlock during the parsing of maliciously crafted tar archives.
This vulnerability can be mitigated by including the following patch after importing the “tarfile” module: https://gist.github.com/sethmlarson/1716ac5b82b73dbcbf23ad2eff8b33e1
Affected
13 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | pypy3 | < python3.13 3.13.6-1 (forky) | python3.13 3.13.6-1 (forky) |
| debian | python2.7 | < python3.13 3.13.6-1 (forky) | python3.13 3.13.6-1 (forky) |
| debian | python3.11 | < python3.13 3.13.6-1 (forky) | python3.13 3.13.6-1 (forky) |
| debian | python3.13 | < python3.13 3.13.6-1 (forky) | python3.13 3.13.6-1 (forky) |
| debian | python3.9 | < python3.13 3.13.6-1 (forky) | python3.13 3.13.6-1 (forky) |
| msrc | azl3_python3_3.12.9-4_on_azure_linux_3.0 | — | — |
| msrc | azl3_tensorflow_2.16.1-9_on_azure_linux_3.0 | — | — |
| msrc | cbl2_python3_3.9.19-14_on_cbl_mariner_2.0 | — | — |
| python_software_foundation | cpython | < 3.10.19 | 3.10.19 |
| python_software_foundation | cpython | >= 3.11.0 < 3.11.14 | 3.11.14 |
| python_software_foundation | cpython | >= 3.12.0 < 3.12.12 | 3.12.12 |
| python_software_foundation | cpython | >= 3.13.0 < 3.13.6 | 3.13.6 |
| python_software_foundation | cpython | >= 3.14.0a1 < 3.14.0rc2 | 3.14.0rc2 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH
vendor_debian7.5HIGH
vendor_msrc7.5HIGH
vendor_redhat7.5HIGH
vendor_oracle6.7HIGH
vendor_ubuntu4.3MEDIUM
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Oracle
Oracle Oracle Database Server Risk Matrix: RDBMS (Python) — CVE-2025-8194
vendor_oracle·2026-01-15·CVSS 6.7
CVE-2025-8194 [HIGH] Oracle Oracle Database Server Risk Matrix: RDBMS (Python) — CVE-2025-8194
Oracle Oracle Database Server Risk Matrix: RDBMS (Python) vulnerability
CVE: CVE-2025-8194
CVSS: 6.7
Protocol: None
Remote exploit: No
Affected versions: Local
Advisory: cpujan2026 (JAN 2026)
Ubuntu
Python 2.7 vulnerability
vendor_ubuntu·2025-08-29·CVSS 4.3
CVE-2025-8194 [MEDIUM] Python 2.7 vulnerability
Title: Python 2.7 vulnerability
Summary: Several security issues were fixed in Python.
USN-7710-1 fixed vulnerabilities in Python. This update provides the
corresponding fix for CVE-2025-8194 for Python 2.7.
Original advisory details:
It was discovered that Python inefficiently parsed maliciously crafted
HTML input. An attacker could possibly use this issue to cause a denial of
service. (CVE-2025-6069)
It was discovered that Python incorrectly parsed maliciously crafted Tar
archives. An attacker could possibly use this issue to cause a denial of
service. (CVE-2025-8194)
Instructions: In general, a standard system update will make all the necessary changes.
Ubuntu
Python vulnerabilities
vendor_ubuntu·2025-08-21·CVSS 4.3
CVE-2025-6069 [MEDIUM] Python vulnerabilities
Title: Python vulnerabilities
Summary: Several security issues were fixed in Python.
It was discovered that Python inefficiently parsed maliciously crafted HTML
input. An attacker could possibly use this issue to cause a denial of
service. (CVE-2025-6069)
It was discovered that Python incorrectly parsed maliciously crafted Tar
archives. An attacker could possibly use this issue to cause a denial of
service. (CVE-2025-8194)
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
cpython: Cpython infinite loop when parsing a tarfile
vendor_redhat·2025-07-28·CVSS 7.5
CVE-2025-8194 [HIGH] CWE-835 cpython: Cpython infinite loop when parsing a tarfile
cpython: Cpython infinite loop when parsing a tarfile
There is a defect in the CPython “tarfile” module affecting the “TarFile” extraction and entry enumeration APIs. The tar implementation would process tar archives with negative offsets without error, resulting in an infinite loop and deadlock during the parsing of maliciously crafted tar archives.
This vulnerability can be mitigated by including the following patch after importing the “tarfile” module: https://gist.github.com/sethmlarson/1716ac5b82b73dbcbf23ad2eff8b33e1
A flaw was found in the Python tarfile module. Processing a specially crafted tar archive, specifically an archive with negative offsets, can cause an infinite loop and deadlock. This issue results in a denial of service in the Python application using the tarfile modu
Microsoft
Tarfile infinite loop during parsing with negative member offset
vendor_msrc·2025-07-08·CVSS 7.5
CVE-2025-8194 [HIGH] CWE-835 Tarfile infinite loop during parsing with negative member offset
Tarfile infinite loop during parsing with negative member offset
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
PSF: PSF
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://
Debian
CVE-2025-8194: pypy3 - There is a defect in the CPython “tarfile” module affecting the “TarFile” extrac...
vendor_debian·2025·CVSS 7.5
CVE-2025-8194 [HIGH] CVE-2025-8194: pypy3 - There is a defect in the CPython “tarfile” module affecting the “TarFile” extrac...
There is a defect in the CPython “tarfile” module affecting the “TarFile” extraction and entry enumeration APIs. The tar implementation would process tar archives with negative offsets without error, resulting in an infinite loop and deadlock during the parsing of maliciously crafted tar archives. This vulnerability can be mitigated by including the following patch after importing the “tarfile” module: https://gist.github.com/sethmlarson/1716ac5b82b73dbcbf23ad2eff8b33e1
Scope: local
bookworm: open
bullseye: open
forky: open
sid: open
trixie: open
OSV
python2.7 vulnerability
osv·2025-08-29·CVSS 4.3
CVE-2025-8194 [MEDIUM] python2.7 vulnerability
python2.7 vulnerability
USN-7710-1 fixed vulnerabilities in Python. This update provides the
corresponding fix for CVE-2025-8194 for Python 2.7.
Original advisory details:
It was discovered that Python inefficiently parsed maliciously crafted
HTML input. An attacker could possibly use this issue to cause a denial of
service. (CVE-2025-6069)
It was discovered that Python incorrectly parsed maliciously crafted Tar
archives. An attacker could possibly use this issue to cause a denial of
service. (CVE-2025-8194)
OSV
python3.13, python3.12, python3.11, python3.10, python3.9, python3.8, python3.7, python3.6, python3.5, python3.4 vulnerabilities
osv·2025-08-21·CVSS 4.3
CVE-2025-6069 [MEDIUM] python3.13, python3.12, python3.11, python3.10, python3.9, python3.8, python3.7, python3.6, python3.5, python3.4 vulnerabilities
python3.13, python3.12, python3.11, python3.10, python3.9, python3.8, python3.7, python3.6, python3.5, python3.4 vulnerabilities
It was discovered that Python inefficiently parsed maliciously crafted HTML
input. An attacker could possibly use this issue to cause a denial of
service. (CVE-2025-6069)
It was discovered that Python incorrectly parsed maliciously crafted Tar
archives. An attacker could possibly use this issue to cause a denial of
service. (CVE-2025-8194)
GHSA
GHSA-v594-44hm-2j7p: There is a defect in the CPython “tarfile” module affecting the “TarFile” extraction and entry enumeration APIs
ghsa_unreviewed·2025-07-28
CVE-2025-8194 [HIGH] CWE-835 GHSA-v594-44hm-2j7p: There is a defect in the CPython “tarfile” module affecting the “TarFile” extraction and entry enumeration APIs
There is a defect in the CPython “tarfile” module affecting the “TarFile” extraction and entry enumeration APIs. The tar implementation would process tar archives with negative offsets without error, resulting in an infinite loop and deadlock during the parsing of maliciously crafted tar archives.
This vulnerability can be mitigated by including the following patch after importing the “tarfile” module:
import tarfile
def _block_patched(self, count):
if count < 0: # pragma: no cover
raise tarfile.InvalidHeaderError("invalid offset")
return _block_patched._orig_block(self, count)
_block_patched._orig_block = tarfile.TarInfo._block
tarfile.TarInfo._block = _block_patched
OSV
CVE-2025-8194: There is a defect in the CPython “tarfile” module affecting the “TarFile” extraction and entry enumeration APIs
osv·2025-07-28·CVSS 7.5
CVE-2025-8194 [HIGH] CVE-2025-8194: There is a defect in the CPython “tarfile” module affecting the “TarFile” extraction and entry enumeration APIs
There is a defect in the CPython “tarfile” module affecting the “TarFile” extraction and entry enumeration APIs. The tar implementation would process tar archives with negative offsets without error, resulting in an infinite loop and deadlock during the parsing of maliciously crafted tar archives. This vulnerability can be mitigated by including the following patch after importing the “tarfile” module: https://gist.github.com/sethmlarson/1716ac5b82b73dbcbf23ad2eff8b33e1
No detection rules found.
No public exploits indexed.
https://gist.github.com/sethmlarson/1716ac5b82b73dbcbf23ad2eff8b33e1https://github.com/python/cpython/commit/57f5981d6260ed21266e0c26951b8564cc252bc2https://github.com/python/cpython/commit/7040aa54f14676938970e10c5f74ea93cd56aa38https://github.com/python/cpython/commit/73f03e4808206f71eb6b92c579505a220942ef19https://github.com/python/cpython/commit/b4ec17488eedec36d3c05fec127df71c0071f6cbhttps://github.com/python/cpython/commit/c9d9f78feb1467e73fd29356c040bde1c104f29fhttps://github.com/python/cpython/commit/cdae923ffe187d6ef916c0f665a31249619193fehttps://github.com/python/cpython/commit/fbc2a0ca9ac8aff6887f8ddf79b87b4510277227https://github.com/python/cpython/issues/130577https://github.com/python/cpython/pull/137027https://mail.python.org/archives/list/[email protected]/thread/ZULLF3IZ726XP5EY7XJ7YIN3K5MDYR2D/http://www.openwall.com/lists/oss-security/2025/07/28/1http://www.openwall.com/lists/oss-security/2025/07/28/2
2025-07-28
Published