Medium Memory corruption

CVE-2026-32249 — NFA regex engine NULL pointer dereference affects Vim < 9.2.0137

Vim is an open source, command line text editor. From 9.1.0011 to before 9.2.0137, Vim's NFA regex compiler, when encountering a collection containing a combining character as the endpoint of a character range (e.g. [0-0\u05bb]), incorrectly emits the composing bytes of that character as separate NFA states. This corrupts the NFA postfix stack, resulting in NFA_START_COLL having a NULL out1 pointer. When nfa_max_width() subsequently traverses the compiled NFA to estimate match width for the look-behind assertion, it dereferences state->out1->out without a NULL check, causing a segmentation fault. This vulnerability is fixed in 9.2.0137.

Published Mar 12, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: GitHub_M

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

EPSS 0.2% (30-day exploitation probability)+1
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

0.19%

ahead of 8% of scored CVEs · Oct 15, 2026

Affects

Vim

CVSS base

5.5

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 (Vim Vim).
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 matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Vim	Vim	≥ 9.1.0011 and < 9.2.0137	Vulnerable	NIST National Vulnerability Database
Vim	Vim	version >= 9.1.0011, < 9.2.0137	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

Local

Attack complexity

Low

Privileges required

None

User interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

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
5.5	CVSS 3.1	Medium	1.8	3.6	nvd@nist.gov via NIST National Vulnerability Database
5.3	CVSS 3.1	Medium	1.8	3.4	security-advisories@github.com via NIST National Vulnerability Database
5.3	CVSS 3.1	Medium	—	—	GitHub_M via CVE Program (cve.org) e CISA ADP

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

Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 5.5 (NVD (NIST)) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-476 · NULL Pointer Dereference

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 15, 2026 · 3 reading(s) · max 0.19%

Detection

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

Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.

endpoint telemetry (EDR)crash dumps

Timeline

What happened to this CVE, newest first.

2026
Affected products added · vim/vim
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
Fix documented
Oct 13, 2026 · NIST National Vulnerability Database
CVSS changed · 5.5
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Analyzed
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
Mar 12, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

3 on the record

github.com/vim/vim/security/advisories/GHSA-9phh-423r-778r
Vendor Advisory, x_refsource_CONFIRM, NIST National Vulnerability Database
github.com/vim/vim/commit/36d6e87542cf823d833e451e09a90ee429899cec
Patch, x_refsource_MISC, NIST National Vulnerability Database
github.com/vim/vim/releases/tag/v9.2.0137
Release Notes, x_refsource_MISC, NIST National Vulnerability Database

Elsewhere on this site

Vim
every CVE for this vendor

Memory corruption
same class

CWE-476
other pages naming this weakness

Related CVEs (same products)

High CVE-2026-43961 Vim: vimscript injection via unescaped filename in netrw s:netrwmarkfile() filter() expression allows arbitrary code execution Aug 19, 2026
High CVE-2026-73073 Vim: Arbitrary Ex Command Execution in C Omni-Completion Aug 18, 2026
High CVE-2026-73077 Vim: Arbitrary Code Execution via Shell Keyword Lookup Aug 11, 2026
High CVE-2026-73078 Vim: Arbitrary Code Execution via Netrw Menu Construction Aug 11, 2026
Medium CVE-2026-73074 Vim: Heap Buffer Overflow in Text Property Handling Aug 11, 2026
Low CVE-2026-73071 Vim: Use-after-free in JSON Decoding Aug 11, 2026

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 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-2026-32249 is "NFA regex engine NULL pointer dereference affects Vim < 9.2.0137", rated Medium. It affects Vim (Vim); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.19% estimates the probability of exploitation in 30 days; neither replaces your asset context. 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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