CVE-2021-28963

Shibboleth Service Provider before 3.2.1 allows content injection because template generation...

5.3 MediumFix available

Shibboleth Service Provider before 3.2.1 allows content injection because template generation uses attacker-controlled parameters.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: None
Integrity: Low
Availability: None

Exploit likelihood

1.31%Up 0.1 points since Apr 14, 2021

What each source reports

NVD Score used 5.3

Shibboleth Service Provider before 3.2.1 allows content injection because template generation uses attacker-controlled parameters.

Record: CVE-2021-28963
CVSS 3.1: 5.3 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CVSS 2.0: 5.0 MediumAV:N/AC:L/Au:N/C:N/I:P/A:N
Weakness: CWE-74
Updated: 2026-11-02

CVE List No score

Shibboleth Service Provider before 3.2.1 allows content injection because template generation uses attacker-controlled parameters.

Record: CVE-2021-28963
Updated: 2026-11-02

EUVDEUVD-2021-15612 No score

Shibboleth Service Provider before 3.2.1 allows content injection because template generation uses attacker-controlled parameters.

Record: EUVD-2021-15612
Updated: 2026-11-03

GitHub AdvisoriesGHSA-6jjj-9g6r-j2vh 5.3

Shibboleth Service Provider before 3.2.1 allows content injection because template generation...

Shibboleth Service Provider before 3.2.1 allows content injection because template generation uses attacker-controlled parameters.

Record: GHSA-6jjj-9g6r-j2vh
CVSS 3.1: 5.3 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Weakness: CWE-74
Updated: 2026-11-02

OSV 5.3

Shibboleth Service Provider before 3.2.1 allows content injection because template generation uses attacker-controlled parameters.

Record: CVE-2021-28963
CVSS 3.1: 5.3 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Updated: 2026-11-02

OSVDEBIAN-CVE-2021-28963 5.3

Shibboleth Service Provider before 3.2.1 allows content injection because template generation uses attacker-controlled parameters.

Record: DEBIAN-CVE-2021-28963
CVSS 3.1: 5.3 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Updated: 2026-11-02

OSVUBUNTU-CVE-2021-28963 5.3

Shibboleth Service Provider before 3.2.1 allows content injection because template generation uses attacker-controlled parameters.

Record: UBUNTU-CVE-2021-28963
CVSS 3.1: 5.3 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Updated: 2026-11-02

OSVUSN-4925-1 No score

shibboleth-sp vulnerability

Toni Huttunen and Fraktal Oy discovered that the Shibboleth Service provider allowed content injection due to allowing attacker-controlled parameters in error or other status pages. An attacker could use this to inject malicious content.

Record: USN-4925-1
Updated: 2026-11-02

Affected products

Affected packages

Affected packages
Package	Affected	Fixed
`shibboleth-sp` Debian:12	before 3.2.1+dfsg1-1	3.2.1+dfsg1-1
`shibboleth-sp` Debian:13	before 3.2.1+dfsg1-1	3.2.1+dfsg1-1
`shibboleth-sp` Debian:14	before 3.2.1+dfsg1-1	3.2.1+dfsg1-1
`shibboleth-sp2` Debian:9	before 2.6.0+dfsg1-4+deb9u2, plus listed versions 2.6.0+dfsg1-42.6.0+dfsg1-4+deb9u12.6.0+dfsg1-4+deb9u1~bpo8+1	2.6.0+dfsg1-4+deb9u2
`shibboleth-sp` Debian:10	before 3.0.4+dfsg1-1+deb10u1, plus listed versions 3.0.4+dfsg1-1	3.0.4+dfsg1-1+deb10u1
`shibboleth-sp2` Ubuntu:16.04:LTS	All versions, plus listed versions 2.5.3+dfsg-2.1build1	None known
`shibboleth-sp2` Ubuntu:18.04:LTS	All versions, plus listed versions 2.6.0+dfsg1-42.6.0+dfsg1-52.6.0+dfsg1-5build12.6.1+dfsg1-12.6.1+dfsg1-2	None known
`shibboleth-sp` Ubuntu:20.04:LTS	before 3.0.4+dfsg1-1ubuntu0.1, plus listed versions 3.0.4+dfsg1-13.0.4+dfsg1-1build1	3.0.4+dfsg1-1ubuntu0.1
`shibboleth-sp` Ubuntu:Pro:22.04:LTS	All versions, plus listed versions 3.2.2+dfsg1-1ubuntu13.3.0+dfsg1-13.3.0+dfsg1-1ubuntu0.1~esm1	None known

History

History
Recorded	Changed	Sources
Nov 3, 2026	aliases	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2021-28963 is a medium vulnerability (CVSS 5.3) in Shibboleth Service Provider, published March 18, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.31%, the 70th percentile. Fixed in shibboleth-sp 3.2.1+dfsg1-1.

References

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