Cross-site Scripting with Markdown rendering in CoCalc

published 2024-05-28 2 y ago modified 2026-06-17 4 mo ago also EUVD-2024-35885

cvss: 7.6; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 35%
public exploits: 0; none known

CoCalc is web-based software that enables collaboration in research, teaching, and scientific publishing. In affected versions the markdown parser allows `<script>` tags to be included which execute when published. This issue has been addressed in commit `419862a9c9879c`. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Patch / fix

fixed in 1 links 1

sagemath cocalc 419862a9c9879c

github.com/sagemathinc/cocalc@419862a commit

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 2 y ago (2024-05-29)

Exploit prediction

0.41% chance of exploitation in the next 30 days, higher than 35% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.6	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:L

Affected products

sagemathinc cocalc
sagemath cocalc

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

CVE List CVE-2024-36109
NVD CVE-2024-36109

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary