CVE Intelligence
Critical Access control

CVE-2026-77459 — Argo CD: AppProject destination-namespace and resource restrictions bypassed by PreDelete/PostDelete resource hooks

Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. From 2.10.0 until 3.3.15, 3.4.10, 3.5.4, and 3.6.0-rc2, Argo CD creates PostDelete resource hooks without applying the AppProject destination and resource authorization checks used during ordinary synchronization. The omitted checks include cluster-scoped and namespaced resource allow/deny lists. A user who can write to an Application's Git repository can commit a delete hook targeting a forbidden namespace, server, group, kind, or resource name, and deletion of the Application causes the application-controller to create that resource with its destination-cluster credentials. The reachable impact is bounded by the controller's cluster access but can include cluster-scoped resources, disallowed namespaces, persistent hook objects, and secondary objects created by a hook Job. PreSync, Sync, PostSync, and SyncFail hooks continue to use the normal project checks. This issue is fixed in versions 3.3.15, 3.4.10, 3.5.4, and 3.6.0-rc2.

Published Oct 13, 2026 · Updated Oct 14, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: GitHub_M

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 0.7% (30-day exploitation probability)+8
  • Technical severity (critical)+10

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
0.72%
ahead of 53% of scored CVEs · Oct 14, 2026
Affects
Argoproj
Argo Cd
CVSS base
9.9
Critical · 2 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
No
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

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.

  1. Identify exposed assets running the affected vendor/product/version combinations (Argoproj Argo Cd).
  2. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  3. Search available logs for exploit probes matching the vulnerability class (access control), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Argoproj Argo Cd version >= 2.10.0, <= 2.14.21version >= 3.0.0, < 3.3.15version >= 3.4.0, < 3.4.10version >= 3.5.0, < 3.5.4version >= 3.6.0-rc1, < 3.6.0-rc2 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
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

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

ScoreVersionSeverityExpl.ImpactScored by
9.9 CVSS 3.1 Critical 3.1 6.0 security-advisories@github.com via NIST National Vulnerability Database
9.9 CVSS 3.1 Critical — — GitHub_M via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H (score shown at the top: security-advisories@github.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-863 · Incorrect Authorization

Other CVEs with this weakness →

Detection

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

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Audit administrative actions and access to resources outside each user’s normal pattern.
web/proxy/WAF logsnetwork IDS/IPSauthentication logsapplication logs

Timeline

What happened to this CVE, newest first.

  • 2026
  • SSVC assessment updated
    Oct 14, 2026 · CVE Program (cve.org) e CISA ADP
  • Affected products added · argoproj/argo-cd
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • CVSS changed · 9.9
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Received
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVE published
    Oct 13, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

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

References

9 on the record

Elsewhere on this site

Argoproj
every CVE for this vendor
Access control
same class
CWE-863
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-55797 Argo CD repo-server command injection via crafted SSH repository SOCKS5 proxy URL 6d
  • CVE-2026-45738 Cross-site Scripting (XSS) in Argoproj Argo Cd Jul 15, 2026
  • CVE-2026-45737 Exposure of Sensitive Information in Argoproj Argo Cd Jul 15, 2026
  • CVE-2026-42880 ArgoCD ServerSideDiff is vulnerable to Kubernetes Secret Extraction May 7, 2026
  • CVE-2026-43824 In Argo CD 3.2.0 before 3.2.11 and 3.3.0 before 3.3.9, ServerSideDiff allows reading… May 1, 2026
  • CVE-2025-59531 Unauthenticated argocd-server panic via a malicious Bitbucket-Server webhook payload Oct 1, 2025

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 fixed version, patch or mitigation documented.
  • 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-2026-77459 is "Argo CD: AppProject destination-namespace and resource restrictions bypassed by PreDelete/PostDelete resource hooks", rated Critical. It affects Argo Cd (Argoproj); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 9.9 describes technical severity. EPSS 0.72% 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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