Medium

CVE-2026-13346 — pip absolute path traversal during download from malicious package indexes

pip would incorrectly handle doubly-encoded package URLs from indexes allowing for files to be installed to arbitrary locations on disk even when installing wheels. This vulnerability requires downloading or installing a package from a malicious package index to succeed, malicious packages alone are not able to exploit this vulnerability. Note that this vulnerability only materially impacts users running `pip download` with the `--only-binary` option as installing source distributions from an untrusted index is already an unsafe operation that executes code during install time.

Published Jul 29, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: PSF

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

—

No EPSS score.

Affects

Pypa

Pip

CVSS base

6.5

Medium · 3 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

Documented patch — github.com (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Pypa Pip, Python Packaging Authority Pip).
The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
Apply the fixed version or the patch documented under Remediation.
Exploitation requires user interaction: tighten email/web filtering and warn affected users.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Pypa	Pip	< 26.2	Vulnerable	NIST National Vulnerability Database
Python Packaging Authority	Pip	< 26.2	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

Low

Privileges required

None

User interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
5.6	CVSS 4.0	Medium	—	—	cna@python.org via NIST National Vulnerability Database
5.6	CVSS 4.0	Medium	—	—	PSF via CVE Program (cve.org) e CISA ADP
6.5	CVSS 3.1	Medium	2.8	3.6	nvd@nist.gov via NIST National Vulnerability Database

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N (score shown at the top: nvd@nist.gov)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-36

Other CVEs with this weakness →

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).

web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

2026
Affected products added · python packaging authority/pip
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 15, 2026
Fix documented
Oct 15, 2026 · NIST National Vulnerability Database
CVSS changed · 6.5
Oct 15, 2026 · NIST National Vulnerability Database
Source status changed · → Analyzed
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Jul 29, 2026 · PSF

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

3 on the record

github.com/pypa/pip/pull/14110
Issue Tracking, Patch, patch, NIST National Vulnerability Database
www.openwall.com/lists/oss-security/2026/07/29/7
Mailing List, Third Party Advisory, NIST National Vulnerability Database
mail.python.org/archives/list/security-announce@python.org/thread/L2BNQGGVQCEV7DROOOR
Mailing List, Third Party Advisory, vendor-advisory, NIST National Vulnerability Database

Elsewhere on this site

Pypa
every CVE for this vendor

CWE-36
other pages naming this weakness

Related CVEs (same products)

Medium CVE-2026-8643 pip can extract console_scripts and gui_scripts outside installation directory Jun 1, 2026
Medium CVE-2026-3219 pip doesn't reject concatenated ZIP and tar archives Apr 20, 2026
Low CVE-2026-1703 Limited path traversal when installing wheel archives Feb 2, 2026
Medium CVE-2021-3572 Improper Input Validation in pip Nov 10, 2021

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No FIRST EPSS score.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-13346 is "pip absolute path traversal during download from malicious package indexes", rated Medium. It affects Pip (Pypa); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.5 describes technical severity. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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