CVE-2026-59879

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• 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

0.57% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 47.2% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/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

NVD analysis status

Analyzed. NVD last modified this record on 2026-07-10.

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

2026-07-08 15:47Z3 MO AGO

Last updated

2026-07-08 19:41Z3 MO AGO

Reserved

2026-07-07

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

High (CVSS 8.7)

CNA CVSS vector

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

Weaknesses

• CWE-190Integer Overflow or WraparoundBase
• CWE-400Uncontrolled Resource ConsumptionClass
• CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')Base
• CWE-1284Improper Validation of Specified Quantity in InputBase
• CWE-1285Improper Validation of Specified Index, Position, or Offset in InputBase

Data version

5.2

Document digest

0161765c7a6650afd6660b1f6e98d2d2bb61b3a766f5c0fc796a2484b3b9b799

• github.comhttps://github.com/immutable-js/immutable-js/security/advisories/GHSA-v56q-mh7h-f735x_refsource_CONFIRM
• github.comhttps://github.com/immutable-js/immutable-js/commit/a1a1ee412dcaa380ab325196283d06594ffe4b84x_refsource_MISC
• github.comhttps://github.com/immutable-js/immutable-js/commit/f0bc997d8eb9886aff2236635aa210a95a04304ax_refsource_MISC
• github.comhttps://github.com/immutable-js/immutable-js/releases/tag/v4.3.9x_refsource_MISC
• github.comhttps://github.com/immutable-js/immutable-js/releases/tag/v5.1.8x_refsource_MISC