CVE-2026-103503

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.20% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 10.6% of scored records. A rank, not a probability.

NVD base score

5.9 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:H/VI:L/VA:N/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

NVD analysis status

Deferred. NVD last modified this record on 2026-10-16.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-10-12 15:17Z16 DAYS AGO

Last updated

2026-10-16 17:32Z12 DAYS AGO

Reserved

2026-10-08

Assigning CNA

EEF

Record state

PUBLISHED

Severity

Medium (CVSS 5.9)

CNA CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

Weaknesses

• CWE-295Improper Certificate ValidationBase

Data version

5.2

Document digest

4ff5555297b9a1ec78dc9499d4bee83f326792722b78590014984324863f60d0

• github.comGitHub Advisoryhttps://github.com/hexpm/hex/security/advisories/GHSA-rw8q-hg7m-cxgrrelatedvendor-advisory
• cna.erlef.orgEEF CNA record for CVE-2026-103503https://cna.erlef.org/cves/CVE-2026-103503.htmlrelated
• osv.devOSV record EEF-CVE-2026-103503https://osv.dev/vulnerability/EEF-CVE-2026-103503related
• github.comIntroducing commit c9b26a4 in hexpm/hexhttps://github.com/hexpm/hex/commit/c9b26a46928bfcd546773571e09c1d05f4cd9fb7related
• github.comFix commit 5f5a213 in hexpm/hexhttps://github.com/hexpm/hex/commit/5f5a2136c7cf5991b6e8a30d645ca9f8e74b0785patch
• github.comFix commit 6232a64 in hexpm/hexhttps://github.com/hexpm/hex/commit/6232a6498015e559743bec4f4fbec9138837cec8patch