BugZero | F5 BugID 677841 - Server SSL TLS session reuse with changed SNI uses...

F5 - Defect ID: 677841

Server SSL TLS session reuse with changed SNI uses incorrect session ID

F5 - Defect ID: 677841

Server SSL TLS session reuse with changed SNI uses incorrect session ID

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: Local Traffic Manager

Description

Symptoms

If an iRule changes the SNI then the wrong session ID will be retrieved (using the original SNI).

Impact

Connection may be rejected by the client if checking at the client occurs (Apache commonly does this). If the client finds that the SNI does not match the SNI in the session information, the connection may be rejected.

Conditions

Occurs when SNI is being modified by an iRule to an SNI that is different from the one specified in the server SSL profile.

Workaround

Disable SSL session cache. This has the side effect of reducing performance.

Fix Information

None

Change history

Links

Original Vendor Announcement

Relevant Products

Click on a version to see all relevant bugs

Affected versions:12.1.2, 12.1.2 hf1, 12.1.2 hf2, 12.1.3, 12.1.3.1, 12.1.3.2, 12.1.3.3, 12.1.3.4, 12.1.3.5, 12.1.3.6, 12.1.3.7, 12.1.4, 12.1.4.1, 12.1.5, 12.1.5.1, 12.1.5.2, 12.1.5.3, 12.1.6, 13.0.0, 13.0.0 hf1, 13.0.0 hf2, 13.0.0 hf3, 13.0.1, 13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3, 13.1.0.4, 13.1.0.5, 13.1.0.6, 13.1.0.7, 13.1.0.8, 13.1.1, 13.1.1.2, 13.1.1.3, 13.1.1.4, 13.1.1.5, 13.1.3, 13.1.3.1, 13.1.3.2, 13.1.3.3, 13.1.3.4, 13.1.3.5, 13.1.3.6, 13.1.4, 13.1.4.1, 13.1.5, 13.1.5.1, 14.0.0, 14.0.0.1, 14.0.0.2, 14.0.0.3, 14.0.0.4, 14.0.0.5, 14.0.1, 14.0.1.1

Fixed versions: 14.1.0

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: 14.1.0

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F5 - Defect ID: 677841

Server SSL TLS session reuse with changed SNI uses incorrect session ID

F5 - Defect ID: 677841

Server SSL TLS session reuse with changed SNI uses incorrect session ID

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: 677841

Server SSL TLS session reuse with changed SNI uses incorrect session ID

F5 - Defect ID: 677841

Server SSL TLS session reuse with changed SNI uses incorrect session ID

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