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CVE.org (no NVD analysis yet)· CNA GitHub_M

CVE-2026-106454: Twisted: IMAP wildcardToRegexp() ReDoS

MediumCVSS 4.3 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 17/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.41% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: azl3 python-twisted 22.10.0-6 on Azure Linux 3.0 22.10.0-7; azl3 python-twisted 22.10.0-7 on Azure Linux 3.0 22.10.0-7.

Low priority for now. Upgrade to azl3 python-twisted 22.10.0-6 on Azure Linux 3.0 22.10.0-7; azl3 python-twisted 22.10.0-7 on Azure Linux 3.0 22.10.0-7 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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.

Published
Oct 6, 2026
Updated
Oct 7, 2026
EPSS
0.4% · 36th percentile

Report tools

JSON

Action score

17

Monitor

Low priority for now.

CVSS
17 / 40 · 4.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.4%

CISA SSVC decision

Exploitation
proof of concept
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
4.3
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-106454

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • twisted twisted

    • <= 25.5.0affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12twistedfrom 0—
Debian:14twistedbefore 26.4.0-526.4.0-5
openSUSE:Tumbleweedpython-Twistedbefore 26.4.0-4.126.4.0-4.1
PyPItwistedup to and including 26.4.0—
PyPItwistedup to and including 25.5.0—

Same product

twisted: all records

Other highest-scoring records for the same primary product.

  • CVE-2020-10109In Twisted Web through 19.10.0, there was an HTTP request splitting vulnerability.
    40Plan
  • CVE-2020-10108In Twisted Web through 19.10.0, there was an HTTP request splitting vulnerability.
    40Plan
  • CVE-2026-115775Twisted: Unauthenticated Remote Denial of Service in the Twisted words domish XML Element Stream via an Unbounded Element Tree
    34Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2024-41810Jul 29, 2024 · HTML injection in HTTP redirect body
    24Monitor
  • ← EarlierCVE-2026-42304May 13, 2026 · Twisted: Denial of Service (DoS) in twisted.names via Crafted DNS Compression Pointer Chains
    30Monitor
  • Later →CVE-2026-115774Oct 23, 2026 · Twisted: Denial of Service in the Twisted IMAP4 Server via a Negative Literal Size in SEARCH
    19Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
azl3 python-twisted 22.10.0-6 on Azure Linux 3.022.10.0-7 · Release NotesMicrosoft (MSRC)
azl3 python-twisted 22.10.0-7 on Azure Linux 3.022.10.0-7 · Release NotesMicrosoft (MSRC)
debian:twisted26.4.0-5 · Debian:14Package registry (OSV)
opensuse:python-Twisted26.4.0-4.1 · openSUSE:TumbleweedPackage registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. Fix recorded+6 d
  3. TodayNov 14, 2026+38 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Not on record for this CVE: researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
low · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
Low

Weakness class (CWE)

CWE-1333 · Inefficient Regular Expression Complexity

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓
  2. SSVC exploitation— → poc
  3. Exploit maturity— → none

For records you follow, these changes also arrive as notifications. →

References

Show all references (2 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records