CVE-2025-4516

mediumpriority · track · 0EPSS 0.002 · 13 %ileDEEUFRRUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.22% (13th) EPSS
CVSS 5.1 · medium
Is it mine?
104 products
Check your exposure
Who says so?
8 sources
cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

There is an issue in CPython when using `bytes.decode("unicode_escape", error="ignore|replace")`. If you are not using the "unicode_escape" encoding or an error handler your usage is not affected. To work-around this issue you may stop using the error= handler and instead wrap the bytes.decode() call in a try-except catching the DecodeError.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

5.9
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 2.1–5.9

v3.15.1mediumCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · CISA US
v3.15.1mediumAV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
v3.15.1mediumCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · Siemens ProductCERT DE
v4.05.9mediumCVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:Nsecondary · ENISA EU
v4.05.9mediumCVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/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:Xsecondary · cna@python.org
v4.02.1lowCVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/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:Xsecondary · CVSS-BT (t0sche)
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-416USCWE-416USCWE-416USCWE-416US
05

affected products (104)

Products and version ranges known to be affected.

showing 20 of 104
06

advisories (10)

Vendor and ecosystem advisories describing this.

  • SSA-089022SSA-089022: Multiple Vulnerabilities in Third-Party Components in SINEC OS before V3.32026-01-28csaf · siemens_psirtDE

    SINEC OS before V3.3 contains third-party components with multiple vulnerabilities. Siemens has released new versions for the affected products and recommends to update to the latest versions.

  • WID-SEC-W-2025-1080CPython: Schwachstelle ermöglicht Denial of ServiceDeutsch2025-05-15csaf · cert_bundDE

    Ein lokaler Angreifer kann eine Schwachstelle in CPython ausnutzen, um einen Denial of Service Angriff durchzuführen.

  • WID-SEC-W-2025-1850Xerox FreeFlow Print Server: Mehrere Schwachstellen ermöglichen nicht spezifizierten AngriffDeutsch2025-08-14csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Xerox FreeFlow Print Server ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.

  • WID-SEC-W-2026-1118Dell PowerProtect Data Domain OS: Mehrere SchwachstellenDeutsch2026-04-14csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Dell PowerProtect Data Domain OS ausnutzen, um beliebigen Code auszuführen – sogar mit Root-Rechten –, um erweiterte Rechte zu erlangen – einschließlich Administratorrechte –, um Sicherheitsmaßnahmen zu umgehen, um Daten zu manipulieren, um vertrauliche Informationen offenzulegen oder um andere, nicht näher spezifizierte Angriffe durchzuführen.

  • ICSA-26-043-06Siemens SINEC OS2026-01-28icsa · cisa_csaf_otUS

    SINEC OS before V3.3 contains third-party components with multiple vulnerabilities. Siemens has released new versions for the affected products and recommends to update to the latest versions.

  • BIT-libpython-2025-4516Use-after-free in "unicode_escape" decoder with error handler2025-08-11vendor · osvUS

    There is an issue in CPython when using `bytes.decode("unicode_escape", error="ignore|replace")`. If you are not using the "unicode_escape" encoding or an error handler your usage is not affected. To work-around this issue you may stop using the error= handler and instead wrap the bytes.decode() call in a try-except catching the DecodeError.

  • BIT-python-2025-4516Use-after-free in "unicode_escape" decoder with error handler2025-06-20vendor · osvUS

    There is an issue in CPython when using `bytes.decode("unicode_escape", error="ignore|replace")`. If you are not using the "unicode_escape" encoding or an error handler your usage is not affected. To work-around this issue you may stop using the error= handler and instead wrap the bytes.decode() call in a try-except catching the DecodeError.

  • BIT-python-min-2025-4516Use-after-free in "unicode_escape" decoder with error handler2025-06-20vendor · osvUS

    There is an issue in CPython when using `bytes.decode("unicode_escape", error="ignore|replace")`. If you are not using the "unicode_escape" encoding or an error handler your usage is not affected. To work-around this issue you may stop using the error= handler and instead wrap the bytes.decode() call in a try-except catching the DecodeError.

  • CERTFR-2026-AVI-1385Multiples vulnérabilités dans les produits VMwareFrançais2026-10-26vendor · certfrFR
  • PSF-2025-42025-05-15vendor · osvUS

    There is an issue in CPython when using `bytes.decode("unicode_escape", error="ignore|replace")`. If you are not using the "unicode_escape" encoding or an error handler your usage is not affected. To work-around this issue you may stop using the error= handler and instead wrap the bytes.decode() call in a try-except catching the DecodeError.

07

also known as (8)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bduosvcert_bundcisa_csaf_otsiemens_psirtcertfrNVDCVE.orgMITRE
published 2025-05-15modified 2026-07-31
09

references (31)

External citations — patches, advisories, analysis.

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