CVE-2026-102521: Out-of-bounds Read (CVSS 8.6)

Description

The decoder in `readFromDataView` in lib0 before 0.2.119 can be tricked into reading more than it should from a buffer. The vulnerability allows reading past the decoders' view, thus exposing adjacent process memory. This can be anything that is currently in the head, for example credentials or logs. This is similar to but different from GHSA-r5c8-rf4w-qrq8.

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CVSS v3.1 Score

8.6

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

EPSS — Exploit Prediction

0.0026

Probability of exploitation

0.16%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-125 Out-of-bounds Read

References

Other References

https://github.com/dmonad/lib0/commit/49383f2716283b90059dbfe01e110c0ab7ef5592 https://github.com/dmonad/lib0/security/advisories/GHSA-g75x-89c3-rvmr

Frequently Asked Questions

What is CVE-2026-102521? +

The decoder in `readFromDataView` in lib0 before 0.2.119 can be tricked into reading more than it should from a buffer. The vulnerability allows reading past the decoders' view, thus exposing adjacent process memory. This can be anything that is currently in the head, for example credentials or logs. This is similar to but different from GHSA-r5c8-rf4w-qrq8. It has a CVSS v3.1 base score of 8.6 (HIGH).

How severe is CVE-2026-102521? +

CVE-2026-102521 has a CVSS v3.1 score of 8.6 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0026, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-102521? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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