BugZero | F5 BugID 958773 - [SAML SP] Assertion canonicalization fails if <Att...

F5 - Defect ID: 958773

[SAML SP] Assertion canonicalization fails if <AttributeValue> contains spaces.

F5 - Defect ID: 958773

[SAML SP] Assertion canonicalization fails if <AttributeValue> contains spaces.

Last updated on July 18th, 2026

BugZero Risk Score
6.7 Medium

Overall: 6.7

Severity: 7.3

Community: 4.2

Lifecycle: 7.0

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Bug Details

Priority: 3-Major
Status: Verified
Impact Category: Access Policy Manager

Description

Symptoms

In /var/log/apm [apmd]modules/Authentication/Saml/SamlSPAgent.cpp: 'verifyAssertionSignature()': 5883: Verification of SAML signature #1 failed [apmd]SAML Agent: /Common/xxxxxx failed to process signed assertion, error: Digest of SignedInfo mismatch

Impact

Verification of SAML signature fails.

Conditions

SAML attribute values have double-byte spaces.

Workaround

Remove double-byte spaces from SAML Attribute values (consult a vendor who populates SAML attribute values for advice on how to remove double-byte spaces).

Fix Information

N/A

Change history

Links

Original Vendor Announcement

Relevant Products

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Affected versions:14.1.0, 14.1.0.1, 14.1.0.2, 14.1.0.3, 14.1.0.5, 14.1.0.6, 14.1.2, 14.1.2.1, 14.1.2.2, 14.1.2.3, 14.1.2.4, 14.1.2.5, 14.1.2.6, 14.1.2.7, 14.1.2.8, 14.1.3, 14.1.3.1, 14.1.4, 14.1.4.1, 14.1.4.2, 14.1.4.3, 14.1.4.4, 14.1.4.5, 14.1.4.6, 14.1.5, 14.1.5.1, 14.1.5.2, 14.1.5.3, 14.1.5.4, 14.1.5.6, 15.1.0, 15.1.0.1, 15.1.0.2, 15.1.0.3, 15.1.0.4, 15.1.0.5, 15.1.1, 15.1.2, 15.1.2.1, 15.1.3, 15.1.3.1, 15.1.4, 15.1.4.1, 15.1.5, 15.1.5.1, 15.1.6, 15.1.6.1, 15.1.7, 15.1.8, 15.1.8.1, 15.1.8.2, 15.1.9, 15.1.9.1, 15.1.10, 15.1.10.2, 15.1.10.3, 15.1.10.4, 15.1.10.5, 15.1.10.6, 15.1.10.7, 15.1.10.8, 16.0.0, 16.0.0.1, 16.0.1, 16.0.1.1, 16.0.1.2, 16.1.1, 16.1.2, 16.1.2.1, 16.1.2.2, 16.1.3, 16.1.3.1, 16.1.3.2, 16.1.3.3, 16.1.3.4, 16.1.3.5, 16.1.4, 16.1.4.1, 16.1.4.2, 16.1.4.3, 16.1.5, 16.1.5.1, 16.1.5.2, 16.1.6, 16.1.6.1, 17.0.0, 17.0.0.1, 17.0.0.2

Fixed versions: 17.1.0

Relevant Products

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Fixed versions: 17.1.0

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F5 - Defect ID: 958773

[SAML SP] Assertion canonicalization fails if <AttributeValue> contains spaces.

F5 - Defect ID: 958773

[SAML SP] Assertion canonicalization fails if <AttributeValue> contains spaces.

Last updated on July 18th, 2026

BugZero Risk Score6.7 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

F5 - Defect ID: 958773

[SAML SP] Assertion canonicalization fails if <AttributeValue> contains spaces.

F5 - Defect ID: 958773

[SAML SP] Assertion canonicalization fails if <AttributeValue> contains spaces.

Last updated on July 18th, 2026

BugZero Risk Score6.7 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
6.7 Medium

BugZero Risk Score
6.7 Medium