5.2

CVE-2026-49860: deno Server-Side Request Forgery (SSRF)

CVSS: 5.2v3.1MediumAnalyzed
AliasesGHSA-83pc-3rw9-qpwj
Published 23-06-2026Last modified 23-06-2026
Open JSON

Vulnerability summary

CVE-2026-49860 is a medium (CVSS 5.2) Server-Side Request Forgery (SSRF) vulnerability in deno. EPSS estimates a 0.14% chance of exploitation in the next 30 days, higher than 3% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.2/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.14%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 23-06-2026
    PublishedVulnerability first disclosed.
  2. 23-06-2026
    Last modifiedVulnerability information updated.

Description

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.8.1, when a WebSocket connection was opened, Deno checked the destination hostname against --deny-net rules but did not re-check the IP addresses that hostname resolved to. An attacker-controlled script could use a specially crafted domain name that passes the hostname check yet resolves to a denied IP, bypassing the network restriction entirely. This vulnerability is fixed in 2.8.1.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.14%

Chance of exploitation in the next 30 days

Percentile

3%

Versus all other CVEs

30-day change

0.00 pp

From 0.14% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.14%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Crates.Io1 product
  • deno< 2.8.1
Deno1 product
Denoland1 product

3 vendors · 3 products

References

3 links