CVE-2026-15310VulnerabilityPublished 19 Oct 2026Updated 26 Oct 2026

SUSE · Security update for python311

Affects SUSESource GCVE Database

Mentioned vulnerabilities

Authoritative record:CVE-2026-15310· Low 2.1

Not known to be exploited · CVSS 2.1 Low · fixed in SUSE package updates : update SUSE CPython when convenient.

Data as of 26 Oct 2026, 21:28 UTC

CVSS 4.0 base score

2.1Low

How severe the flaw is on the 0–10 CVSS scale.

Patch: Available – fixed in 3.15.0rc2, 3.14.8, 3.13.16 +3

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: Present
Privileges Required: None
User Interaction: Active
Vulnerable system confidentiality: None
Vulnerable system integrity: None
Vulnerable system availability: Low
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: Present: The successful attack depends on the presence of specific deployment and execution conditions of the vulnerable system that enable the attack. These include: a race condition must be won to successfully exploit the vulnerability (the successfulness of the attack is conditioned on execution conditions that are not under full control of the attacker, or the attack may need to be launched multiple times against a single target before being successful); the attacker must inject themselves into the logical network path between the target and the resource requested by the victim (e.g. vulnerabilities requiring an on-path attacker).
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
User Interaction: Active: Successful exploitation of this vulnerability requires a targeted user to perform specific, conscious interactions with the vulnerable system and the attacker’s payload, or the user’s interactions would actively subvert protection mechanisms which would lead to exploitation of the vulnerability.
Vulnerable system confidentiality: None: There is no loss of confidentiality within the Vulnerable System.
Vulnerable system integrity: None: There is no loss of integrity within the Vulnerable System.
Vulnerable system availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the Vulnerable System are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 25 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
Python Software FoundationCPython	Affected >=3.15.0a1 <3.15.0rc2	Fixed in 3.15.0rc2
Python Software FoundationCPython	Affected >=3.14.0 <3.14.8	Fixed in 3.14.8
Python Software FoundationCPython	Affected >=3.13.0 <3.13.16	Fixed in 3.13.16
Python Software FoundationCPython	Affected >=3.12.0 <3.12.15	Fixed in 3.12.15
Python Software FoundationCPython	Affected >=3.11.0 <3.11.17	Fixed in 3.11.17
Python Software FoundationCPython	Affected <3.10.22	Fixed in 3.10.22

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

Description

This update for python311 fixes the following issues: - CVE-2026-15310: memory exhaustion in zipfile in bzip2/LZMA/Zstandard decompression (bsc#1277111). - CVE-2026-15806: urllib.request.HTTPPasswordMgr credentials for one URL scheme sent over another scheme (bsc#1276223). - CVE-2026-17084: StringPrep algorithm considered Unicode codepoint attributes outside Unicode 3.2.0 (bsc#1276226). - CVE-2026-19445: reassigned SNI callbacks with unreferenced SSLContext instances can cause use-after-free (bsc#1283969). - CVE-2026-19553: omitted server_hostname arguments in wrap_bio() can cause silent hostname verification bypasses (bsc#1283826). - CVE-2026-19672: tarfile extraction filter bypass allows creation of directories outside the destination (bsc#1276227). - CVE-2026-82049: tarfile extraction filters mishandle archives containing a hard link to a symbolic link, allowing file modification and content disclosure (bsc#1280459). Changes for python311: - Update to 3.11.17: - Security - gh-158446: Fix a crash or incorrect output that could occur when formatting a float or complex with a precision close to the platform's INT_MAX. PyOS_double_to_string() now raises ValueError for any precision of that magnitude, regardless of presentation type or value, as the format string parsers already did for precisions above INT_MAX. - gh-157190: Fixed a vulnerability in the tarfile data and tar extraction filters where a crafted archive using a hard link to a symbolic link could change the permissions and modification time of a file outside the destination directory, and expose its contents inside the extracted tree. This addresses CVE 2026-82049. (bsc#1280459, CVE-2026-82049) - gh-156793: asyncio: loop.start_tls() and loop.create_connection() now validate the server_hostname argument if an ssl.SSLContext is passed with check_hostname set to True, emitting DeprecationWarning if server_hostname is missing. (This will raise ValueError in Python 3.13 and later.) (bsc#1283826, CVE-2026-19553) - gh-156793: ssl.SSLContext.wrap_bio() now validates its server_side, server_hostname and session arguments similar to ssl.SSLContext.wrap_socket(), but for backward compatiblity reasons emits DeprecationWarning instead of ValueError. In particular, a context with check_hostname enabled and no server_hostname passed to wrap_bio() now emits DeprecationWarning to indicate the hostname wasn't checked. (In Python 3.13 and later, this raises ValueError.) - gh-157265: In tarfile, when extracting a link falls back to extracting a member of the archive, skip the member when the filter function returns None when called with the extracted member's name replaced with the link's. - gh-157953: Update bundled libexpat to version 2.8.5. - gh-156002: Bound the amount of data zipfile decompresses per read for members compressed with bzip2, LZMA, or Zstandard, matching the existing limit for deflate. A small archive member could previously expand into an unbounded allocation even when read in small chunks. (bsc#1277111, CVE-2026-15310) - gh-155999: Fix the tarfile tar and data extraction filters creating directories outside the destination for members whose name leaves the destination and returns to it, such as ../evil/../dest/sub/file. The containment check used the resolved path, but intermediate directories were created from the name as given. (bsc#1276227, CVE-2026-19672) - gh-156293: Fix a crash in ssl when an sni_callback switches a connection to another SSLContext and the context that carries the callback is no longer referenced by the application. Servers that keep their sni_callback context alive (the usual case when it wraps the listening socket or is stored on the server object) were not affected. This addresses CVE-2026-19445. (bsc#1283969, CVE-2026-19445) - gh-155292: Change the stringprep module and encodings.idna codec to not consider Unicode codepoint attributes beyond those defined in RFC 3454. (bsc#1276226, CVE-2026-17084) - gh-155694: Fix CVE-2026-15806 by scoping HTTPPasswordMgr credentials to the URL scheme, preventing credentials stored for an HTTPS URL from being used for a matching HTTP URL, while URIs without a scheme continue to match any scheme. (bsc#1276223, CVE-2026-15806) - Library - gh-156002: zipfile again reads members through a third-party decompressor installed by monkey-patching the private _get_decompressor() to return an object that only implements old BZ2Decompressor API from Python 3.3. Note that decompressors without needs_input and two-argument decompress() are vulnerable to CVE 2026-15310. - gh-156353: Fix configparser parsing when using whitespace in delimiters. - Build - gh-155757: Set the --argv0 argument to wasmtime for WASI builds so the test suite passes. Otherwise the calculated paths to the stdlib for frozen modules is incorrect. - CVE-2026-15310: bound zipfile decompression for bzip2/LZMA (bsc#1277111, gh#python/cpython#156002)

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