Twisted is an event-based framework for internet applications, supporting Python 3.6+. In 25.5.0 and earlier, wildcardToRegexp() in twisted/mail/imap4.py translates the IMAP asterisk and percent wildcards but passes all other characters from an authenticated client's LIST or LSUB pattern directly to re.compile(), allowing nested or otherwise expensive regular expression constructs to cause catastrophic backtracking when matched against mailbox names. Because Twisted uses a cooperative single-threaded reactor, the blocking match suspends all server input and output for the duration of the match. No fixed release is available as of this review.
CVE-2026-106454
MEDIUMPre-NVD 4.34.3—Trending — 3 sources updated this weekElevated
EchelonGraph scoreHIGH confidence
Score 4.3 from GitHub Security Advisory published 2026-10-07. A secondary CVSS source baseline 4.3; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, secondary
4.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: —CVSS: 4.3Exploit: Elevated riskExposed services: Not assessed
A fixed version is listed under Patch Availability — apply it.
- CVSS v3
- 4.3
- EG Score
- 4.3MEDIUMhigh confidence
- EG Risk
- 35EG Risk 35/100CISA SSVC
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity43% × 45%Exploitation40% × 40%Automatability0% × 15%CISA SSVC: Track at low or medium mission impact; Track* at high (mission-essential systems).Action: A fixed version is listed under Patch Availability. Apply it within your standard update timelines. - EPSS PROB
- —
- EPSS %ILE
- —
- KEV
- Not listed
CISA SSVCTrack at low or medium mission impact; Track* at high (mission-essential systems).
A fixed version is listed under Patch Availability. Apply it within your standard update timelines.
Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table
Published
October 6, 2026
Last Modified
October 7, 2026
Advisory Details (3)
Auto-updated Oct 6, 2026🔬 Proof of concept available. Fixed version listed under Patch Availability. Sources: github, github_pr, github_commit.
github_commit
commit 2f8a3c29246f (twisted/twisted)
Fix landed in twisted/twisted commit 2f8a3c29246f — awaiting tagged release
https://github.com/twisted/twisted/commit/2f8a3c29246f4eb324690e06a9767a11dc4aec9fgithub_pr
#12787 imap redos
Fix merged in twisted/twisted PR #12788 on 2026-08-15 — awaiting tagged release
https://github.com/twisted/twisted/pull/12788githubMentions a patch (unverified)🟡 PoC Available
Twisted ≤ 25.5.0: IMAP wildcardToRegexp() ReDoS · Advisory · twisted/twisted · GitHub
https://github.com/twisted/twisted/security/advisories/GHSA-8pqf-f4m5-798gVendor Advisories for CVE-2026-106454(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Patch Availability(1)
| Vendor / Ecosystem | Fix (by version range) / Patch | Released | Source |
|---|---|---|---|
| pip | Twisted | — | ghsa |
Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.
Affected Packages
(1 across 1 ecosystem)
PyPI(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| twisted | 1.0.1 ... 9.0.0 (109 versions) |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 7× in last 7d / 7× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-10-07 17:39 UTCEG score recompute
- 2026-10-07 17:39 UTCGHSA enrichment
- 2026-10-07 16:44 UTCEG score recompute
- 2026-10-07 16:44 UTCGHSA enrichment
- 2026-10-06 20:32 UTCEG score recompute
- 2026-10-06 20:02 UTCEG score recompute
- 2026-10-06 20:01 UTCMITRE cvelistV5first tracked
Related CVEs(same product + same CWE)
Same product
10 shownPyPI:twisted
Frequently asked(4)
What is CVE-2026-106454?
CVE-2026-106454 is a medium vulnerability published on October 6, 2026. Twisted is an event-based framework for internet applications, supporting Python 3.6+. In 25.5.0 and earlier, wildcardToRegexp() in twisted/mail/imap4.py translates the IMAP asterisk and percent wildcards but passes all other characters from an authenticated client's LIST or LSUB pattern directly…
When was CVE-2026-106454 disclosed?
CVE-2026-106454 was first published on October 6, 2026, with the most recent update on October 7, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
What is the CVSS score of CVE-2026-106454?
CVE-2026-106454 has a CVSS base score of 4.3 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-106454?
A fixed version for CVE-2026-106454 is listed under Patch Availability on this page: update to the version listed for your package. The vendor advisories EchelonGraph has for CVE-2026-106454 are linked in the Vendor Advisories panel on this page.
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-106454
Is Your Infrastructure Affected by CVE-2026-106454?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.