Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2026-31976

31
FAUCET Score

CVE-2026-31976 details a critical supply chain compromise (tag poisoning, CWE-506) affecting the xygeni/xygeni-action GitHub Action. An attacker, using compromised GitHub App credentials, manipulated the mutable @v5 tag to point to a malicious commit containing obfuscated shell code. This vulnerability carries a CVSS score of 9.8 (Critical) due to its network-based attack vector, low complexity, and lack of required privileges or user interaction, enabling arbitrary command execution and C2 implant deployment on CI runners with high impact on confidentiality, integrity, and availability. Despite its severity, there is currently no evidence of active exploitation, public exploit code, or significant community/media attention, as indicated by its absence from the CISA KEV catalog and a very low EPSS score.

Impacted Technologies

VendorProductVersion(s)CPE
>= 5.38.0, <= 6.4.0CPE matchmatch criteria
cpe:2.3:a:xygeni:xygeni-action:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 4.0

9.3CRITICAL

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
VS Confidentiality
HIGH
VS Integrity
HIGH
VS Availability
HIGH
SS Confidentiality
NONE
SS Integrity
NONE
SS Availability
NONE
Exploit Maturity
NOT_DEFINED
CvssVersion
4.0

Exploit Intelligence

EPSS Score
0.50%
Probability of exploitation in next 30 days
EPSS Percentile
39.7%
Percentile rank of EPSS score among Peer Group
As of 2026-07-25
Model: v2026.06.15
This CVE's current EPSS score of 0.0050 is in the 18th percentile among its peer group of 36,833 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.3 Bluesky, 0.3 Mastodon, and 2.4 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (1)

actionspatch availablevia ghsa
Product: xygeni/xygeni-actionFixed in: 6.4.0

Vendor Advisories (1)

actionsGHSA-f8q5-h5qh-33mhcritical

xygeni-action v5 tag poisoned with C2 backdoor

Mar 11, 2026

References

github.com / xygeni/xygeni-action/issues/54
Issue Tracking
github.com / xygeni/xygeni-action/security/advisories/GHSA-f8q5-h5qh-33mh
PatchVendor Advisory