🛡️ CVE-2021-42656 — sscms

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs low-level privileges on the target. A user must be tricked into taking some action. The scope is changed, meaning a successful attack can affect components beyond the vulnerable one. Rated impact: confidentiality low, integrity low, availability none.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

• Attack vector: Network — reachable from anywhere that can route to the service.
• Attack complexity: Low — the attack works reliably, with no preparation.
• Privileges required: Low — an ordinary user account is enough.
• User interaction: Required — someone has to click, open or visit something.
• Scope: Changed — a successful attack reaches components beyond the vulnerable one.
• Confidentiality impact: Low — limited, and the attacker does not choose what is affected.
• Integrity impact: Low — limited, and the attacker does not choose what is affected.
• Availability impact: None.

Weakness class

CVE-2021-42656 is classified as CWE-79: Cross-site Scripting (XSS). User-supplied data is written into a page without escaping, so attacker script runs in the browser of anyone who views it.

Affected software

CVE-2021-42656 is recorded against 1 package.

• sscms

Timeline and source

Published on 25 May 2022 and last revised on 8 November 2023. No public exploit is currently recorded for this entry. Record sourced from OSV.

References

nvd.nist.gov (Advisory)
github.com (Web)
github.com (Package)

Other advisories for this package

sscms has other advisories on record. If you are patching this one, these are worth checking on the same host:

• CVE-2025-52237 (6.5 Medium, published 5 Aug 2025)
• CVE-2023-43953 (5.4 Medium, published 3 Oct 2023)
• CVE-2023-43952 (5.4 Medium, published 3 Oct 2023)
• CVE-2023-43951 (5.4 Medium, published 3 Oct 2023)
• CVE-2023-2862 (published 24 May 2023)
• CVE-2022-30349 (published 3 Jun 2022)
• CVE-2021-42655 (8.0 High, published 25 May 2022)
• CVE-2019-11401 (8.0 High, published 24 May 2022)

Same weakness in other software

These advisories are the same class of weakness (CWE-79: Cross-site Scripting (XSS)) in other software:

• CVE-2011-4924 (published 9 Jul 2026)
• CVE-2017-1000482 (published 9 Jul 2026)
• CVE-2021-3988 (published 7 Jul 2026)
• CVE-2017-20182 (published 7 Jul 2026)
• CVE-2014-0157 (published 6 Jul 2026)
• CVE-2017-1000426 (published 6 Jul 2026)
• CVE-2018-25045 (published 6 Jul 2026)
• CVE-2013-2209 (published 6 Jul 2026)

Details

Affected Packages

References