View at Official ubuntu advisory, NVD, CVE.org · CVE detail
Freshness: upstream tracker timestamp is available; use API updated time as primary recency signal.
CVE-2011-0491 medium priority: Ubuntu including 1 source packages (tor), 8 status rows across 8 suites (dapper, hardy, karmic, lucid, maverick, natty, oneiric, upstream): DNE 3, ignored 2, not-affected 2, released 1.
The tor_realloc function in Tor before 0.2.1.29 and 0.2.2.x before 0.2.2.21-alpha does not validate a certain size value during memory allocation, which might allow remote attackers to cause a denial of service (daemon crash) via unspecified vectors, related to "underflow errors."