Which versions are affected?

Affected product and version evidence is listed in the product table above. Current public advisories should be checked for exact version scope before patch targeting is finalized.

Is there active exploitation?

Active exploitation is not confirmed from current sources for CVE-2026-43961. If exploitation is not confirmed from current sources, teams should document that status and continue monitoring KEV, vendor, and telemetry updates.

No. CVE-2026-43961 is not listed in CISA KEV in the supplied enrichment data. KEV status should be monitored because it can change after initial disclosure or after exploitation becomes publicly confirmed.

Is there a public exploit?

1 public PoC repositories reported; 0 marked weaponized in current dataset. Public exploit or PoC availability should raise triage priority, especially for exposed or business-critical systems.

How can defenders detect it?

Start with EDR process telemetry, host service logs where available. Look for vulnerability-class behavior, product errors, suspicious authentication events, exploit probes, and abnormal process activity based only on evidence that applies to the affected product.

How should teams prioritize it?

Prioritize CVE-2026-43961 using CVSS 7.8, EPSS 0%, KEV status, public PoC status, and asset exposure. Internet-facing, privileged, or business-critical deployments should be handled first.

Are workarounds available?

The supplied mitigation guidance says to apply vendor patches and restrict external exposure until fixed. Fixed-version evidence is listed in the mitigation section above.

Which threat actors are linked publicly?

No public threat actor linkage is confirmed from current sources. Do not attribute exploitation to a threat actor unless the source evidence explicitly supports that linkage.

What should be done in the next 24 hours?

Identify exposed assets running affected vendor/product/version combinations. Prioritize based on EPSS, PoC availability, and external exposure. Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class. Open remediation tickets with affected assets, owners, evidence status, and detection coverage so decisions are traceable.

highRemote Code Execpublic exploit

CVE-2026-43961

CVE-2026-43961 — Vim: vimscript injection via unescaped filename in netrw s:netrwmarkfile() filter() expression allows arbitrary code execution

A flaw was found in Vim's netrw plugin. A crafted filename containing quote characters and expression fragments can break out of the quoted context during mark/unmark operations, allowing arbitrary Vimscript execution. This can be leveraged to run shell commands with the privileges of the user running Vim.

Published Aug 19, 2026Updated Aug 19, 2026Sources: NVD, Red Hat (CNA), GitHub, Red Hat (VEX), SOCRadar CTI

Triage

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

Exploitation

Exploit code

public exploit, none observed

EPSS

ahead of 3% of scored CVEs

Affects

Red Hat

6 products listed

CVSS base

7.8

high

CISA SSVC assessment

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

CISA

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script all four kill-chain steps

Technical impact

Total

partial · total control of the vulnerable component

Remediation

The vendor's own words where we have them.

Upgrade Red Hat Enterprise Linux 10 to a fixed release. Apply vendor patches per advisory and restrict external exposure of the affected component until patched.

Red Hat VEX · CVE-2026-43961

fixed0affected0not affected0

First 24 hours

Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.

Identify exposed assets running affected vendor/product/version combinations.
Prioritize based on EPSS, PoC availability, and external exposure.
Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.

Affected scope

Vendor, product and version as the advisories word them.

Vendor	Product	Versions	Status
Red Hat	Red Hat Enterprise Linux 10	—	Vulnerable
Red Hat	Red Hat Enterprise Linux 6	—	Vulnerable
Red Hat	Red Hat Enterprise Linux 7	—	Vulnerable
Red Hat	Red Hat Enterprise Linux 8	—	Vulnerable
Red Hat	Red Hat Enterprise Linux 9	—	Vulnerable
Red Hat	Red Hat OpenShift Container Platform 4	—	Vulnerable

Attack characteristics

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

Availability

High

Confidentiality

High

Integrity

High

Scope

Unchanged

Attack Complexity

Low

Attack Vector

Local

Privileges Req

None

User Interaction

Required

Every base score collected

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

Score	Version	Severity	Expl.	Impact	Source
7.8	CVSS 3.1	high	1.8	5.9	Red Hat (CNA), Red Hat (VEX)

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

What this weakness leads to

MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.

MITRE

CWE-94 · Improper Control of Generation of Code ('Code Injection')

Bypass Protection Mechanism
Gain Privileges or Assume Identity
Execute Unauthorized Code or Commands
Hide Activities

Mitigation: Refactor your program so that you do not have to dynamically generate code.

Weakness & attack patterns

CWE-94Code Injection

Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.

CAPEC-242 · Code InjectionCAPEC-77 · Manipulating User-Controlled VariablesCAPEC-35 · Leverage Executable Code in Non-Executable Files

T1027.006Obfuscated Files or Information: HTML Smuggling
T1027.009Obfuscated Files or Information: Embedded Payloads
T1564.009Hide Artifacts: Resource Forking

Public exploit

Capability, not use: code existing is a different claim from anyone running it.

Repositories

Social mentions

Posts naming this CVE. Attention, not evidence of exploitation — it spikes on disclosure and decays whether or not anything is exploited.

Ubuntu issued security fixes for Vim to address CVE-2026-43961 and CVE-2026-46483, arbitrary code execution flaws affecting Ubuntu 14.04 through 26.04 LTS releases, according to security notice USN-8415-1. https://t.co/RqDNon38lv
@threatcluster· Jun 10, 2026

Detection

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

Search application, proxy, and WAF logs for requests touching /unmark.
Monitor for scanner or exploit-pattern traffic after 1 public PoC repositories were reported.

EDR process telemetryhost service logs

Timeline

What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.

2026
Added · CVSS 3.1 7.8 (AV:L)
Aug 19, 2026 · NVD
Initial · CVE published
Aug 19, 2026 · NVD
Reported · Made public.
Aug 19, 2026 · Red Hat
Reported to Red Hat.
Apr 21, 2026 · Red Hat

Source activity

Readings a source repeats on a schedule, counted rather than listed.

2×Tweets · 1 time tweeted.Jun 10, 2026 – Jun 11, 2026 · SOCRadar CTI
1×SVRS is calculatedJun 11, 2026 · SOCRadar CTI

References

6 on the record

access.redhat.com/security/cve/CVE-2026-43961
Vendor Advisory
bugzilla.redhat.com/show_bug.cgi?id=2460434
Vendor Advisory, Mitre
github.com/vim/vim/security/advisories/GHSA-66hr-7p6x-x5j3
Exploit, Third Party Advisory
www.openwall.com/lists/oss-security/2026/05/14/7
Vendor Advisory
www.cve.org/CVERecord?id=CVE-2026-43961
Vendor Advisory
nvd.nist.gov/vuln/detail/CVE-2026-43961
NVD

Coverage

3 stories from the feeds we poll

Elsewhere on this site

Red Hatevery CVE for this vendor
Remote Code Execsame class
CWE-94other pages naming this weakness

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 record1

What should defenders know first?

CVE-2026-43961 is Vim: vimscript injection via unescaped filename in netrw s:netrwmarkfile() filter() expression allows arbitrary code execution, a high vulnerability affecting Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 from Red Hat. The current evidence does not list it in CISA KEV, and the exploit status is: Active exploitation is not confirmed from current sources for CVE-2026-43961. Public exploit evidence is: 1 public PoC repositories reported; 0 marked weaponized in current dataset. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 7.8 describes technical severity, while EPSS 0% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.