Bug 1849743 - botan: CBC padding operations were not constant time and as a result would leak the length of the plaintext values which were being padded
Summary: botan: CBC padding operations were not constant time and as a result would le...
Keywords:
Status: CLOSED UPSTREAM
Alias: None
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
URL:
Whiteboard:
Depends On: 1849744 1849745 1849746 1849747
Blocks:
TreeView+ depends on / blocked
 
Reported: 2020-06-22 17:28 UTC by Michael Kaplan
Modified: 2020-06-22 23:20 UTC (History)
2 users (show)

Fixed In Version: botan 2.14.0
Clone Of:
Environment:
Last Closed: 2020-06-22 23:20:28 UTC
Embargoed:


Attachments (Terms of Use)

Description Michael Kaplan 2020-06-22 17:28:19 UTC
The CBC padding operations were not constant time and as a result would leak the length of the plaintext values which were being padded to an attacker running a side channel attack via shared resources such as cache or branch predictor. No information about the contents was leaked, but the length alone might be used to make inferences about the contents. This issue affects TLS CBC ciphersuites as well as CBC encryption using PKCS7 or other similar padding mechanisms. In all cases, the unpadding operations were already constant time and are not affected. 

Fixed in 2.14.0, all prior versions affected.

Comment 1 Michael Kaplan 2020-06-22 17:28:45 UTC
Created botan tracking bugs for this issue:

Affects: epel-all [bug 1849747]
Affects: fedora-all [bug 1849744]


Created botan2 tracking bugs for this issue:

Affects: epel-8 [bug 1849746]
Affects: fedora-all [bug 1849745]

Comment 2 Product Security DevOps Team 2020-06-22 23:20:28 UTC
This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.


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