CVE-2021-21240
published 2021-02-08CVE-2021-21240: httplib2 is a comprehensive HTTP client library for Python. In httplib2 before version 0.19.0, a malicious server which responds with long series of "\xa0"…
PriorityP340high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
3.88%
89.2th percentile
httplib2 is a comprehensive HTTP client library for Python. In httplib2 before version 0.19.0, a malicious server which responds with long series of "\xa0" characters in the "www-authenticate" header may cause Denial of Service (CPU burn while parsing header) of the httplib2 client accessing said server. This is fixed in version 0.19.0 which contains a new implementation of auth headers parsing using the pyparsing library.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | python-httplib2 | < python-httplib2 0.20.2-1 (bookworm) | python-httplib2 0.20.2-1 (bookworm) |
| httplib2 | httplib2 | < 0.19.0 | 0.19.0 |
| httplib2 | httplib2 | >= 0 < 0.19.0 | 0.19.0 |
| httplib2_project | httplib2 | < 0.19.0 | 0.19.0 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
osv7.5HIGH
vendor_debian7.5HIGH
vendor_redhat7.5HIGH
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Red Hat
python-httplib2: Regular expression denial of service via malicious header
vendor_redhat·2021-01-09·CVSS 7.5
CVE-2021-21240 [HIGH] CWE-400 python-httplib2: Regular expression denial of service via malicious header
python-httplib2: Regular expression denial of service via malicious header
httplib2 is a comprehensive HTTP client library for Python. In httplib2 before version 0.19.0, a malicious server which responds with long series of "\xa0" characters in the "www-authenticate" header may cause Denial of Service (CPU burn while parsing header) of the httplib2 client accessing said server. This is fixed in version 0.19.0 which contains a new implementation of auth headers parsing using the pyparsing library.
An uncontrolled resource consumption flaw as found in python-httplib2, due to a flawed regular expression used while parsing the WWW-Authenticate header in an HTTP response. This flaw allows a malicious or compromised server to reply with a crafted sequence of characters in the WWW-Authenticate
Debian
CVE-2021-21240: python-httplib2 - httplib2 is a comprehensive HTTP client library for Python. In httplib2 before v...
vendor_debian·2021·CVSS 7.5
CVE-2021-21240 [HIGH] CVE-2021-21240: python-httplib2 - httplib2 is a comprehensive HTTP client library for Python. In httplib2 before v...
httplib2 is a comprehensive HTTP client library for Python. In httplib2 before version 0.19.0, a malicious server which responds with long series of "\xa0" characters in the "www-authenticate" header may cause Denial of Service (CPU burn while parsing header) of the httplib2 client accessing said server. This is fixed in version 0.19.0 which contains a new implementation of auth headers parsing using the pyparsing library.
Scope: local
bookworm: resolved (fixed in 0.20.2-1)
bullseye: open
forky: resolved (fixed in 0.20.2-1)
sid: resolved (fixed in 0.20.2-1)
trixie: resolved (fixed in 0.20.2-1)
GHSA
Regular Expression Denial of Service (REDoS) in httplib2
ghsa·2021-02-08
CVE-2021-21240 [HIGH] CWE-400 Regular Expression Denial of Service (REDoS) in httplib2
Regular Expression Denial of Service (REDoS) in httplib2
### Impact
A malicious server which responds with long series of `\xa0` characters in the `www-authenticate` header may cause Denial of Service (CPU burn while parsing header) of the httplib2 client accessing said server.
### Patches
Version 0.19.0 contains new implementation of auth headers parsing, using pyparsing library.
https://github.com/httplib2/httplib2/pull/182
### Workarounds
```py
import httplib2
httplib2.USE_WWW_AUTH_STRICT_PARSING = True
```
### Technical Details
The vulnerable regular expression is https://github.com/httplib2/httplib2/blob/595e248d0958c00e83cb28f136a2a54772772b50/python3/httplib2/__init__.py#L336-L338
The section before the equals sign contains multiple overlapping groups. Ignoring the optional pa
OSV
CVE-2021-21240: httplib2 is a comprehensive HTTP client library for Python
osv·2021-02-08·CVSS 7.5
CVE-2021-21240 [HIGH] CVE-2021-21240: httplib2 is a comprehensive HTTP client library for Python
httplib2 is a comprehensive HTTP client library for Python. In httplib2 before version 0.19.0, a malicious server which responds with long series of "\xa0" characters in the "www-authenticate" header may cause Denial of Service (CPU burn while parsing header) of the httplib2 client accessing said server. This is fixed in version 0.19.0 which contains a new implementation of auth headers parsing using the pyparsing library.
OSV
Regular Expression Denial of Service (REDoS) in httplib2
osv·2021-02-08
CVE-2021-21240 [HIGH] Regular Expression Denial of Service (REDoS) in httplib2
Regular Expression Denial of Service (REDoS) in httplib2
### Impact
A malicious server which responds with long series of `\xa0` characters in the `www-authenticate` header may cause Denial of Service (CPU burn while parsing header) of the httplib2 client accessing said server.
### Patches
Version 0.19.0 contains new implementation of auth headers parsing, using pyparsing library.
https://github.com/httplib2/httplib2/pull/182
### Workarounds
```py
import httplib2
httplib2.USE_WWW_AUTH_STRICT_PARSING = True
```
### Technical Details
The vulnerable regular expression is https://github.com/httplib2/httplib2/blob/595e248d0958c00e83cb28f136a2a54772772b50/python3/httplib2/__init__.py#L336-L338
The section before the equals sign contains multiple overlapping groups. Ignoring the optional pa
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://github.com/httplib2/httplib2/commit/bd9ee252c8f099608019709e22c0d705e98d26bchttps://github.com/httplib2/httplib2/pull/182https://github.com/httplib2/httplib2/security/advisories/GHSA-93xj-8mrv-444mhttps://pypi.org/project/httplib2https://github.com/httplib2/httplib2/commit/bd9ee252c8f099608019709e22c0d705e98d26bchttps://github.com/httplib2/httplib2/pull/182https://github.com/httplib2/httplib2/security/advisories/GHSA-93xj-8mrv-444mhttps://pypi.org/project/httplib2
2021-02-08
Published