CVE-2026-54743

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.
• 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

0.54% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 45.5% of scored records. A rank, not a probability.

NVD base score

6.4 (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:P/VC:N/VI:N/VA:N/SC:H/SI:H/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 2026-09-09.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

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

2026-08-19 20:18Z2 MO AGO

Last updated

2026-08-21 18:17Z2 MO AGO

Reserved

2026-06-15

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

Medium (CVSS 6.4)

CNA CVSS vector

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

Weaknesses

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')Base

Data version

5.2

Document digest

1cc40818884f05c1b53b94a7322047a20939e1c68cb3a9486e82b52c0fb255a1

• github.comhttps://github.com/LemmyNet/lemmy/security/advisories/GHSA-2g66-9fr3-ppwjx_refsource_CONFIRM
• github.comhttps://github.com/LemmyNet/lemmy-ui/pull/4213x_refsource_MISC
• github.comhttps://github.com/LemmyNet/lemmy-ui/commit/81a3fe07f2a5acc11188320534aa6bf937ebf7ffx_refsource_MISC
• github.comhttps://github.com/LemmyNet/lemmy/releases/tag/0.19.19-beta.1x_refsource_MISC