CVE-2017-1000112 | Date: (C)2017-10-06 (M)2024-04-19 |
Linux kernel: Exploitable memory corruption due to UFO to non-UFO path switch. When building a UFO packet with MSG_MORE __ip_append_data() calls ip_ufo_append_data() to append. However in between two send() calls, the append path can be switched from UFO to non-UFO one, which leads to a memory corruption. In case UFO packet lengths exceeds MTU, copy = maxfraglen - skb->len becomes negative on the non-UFO path and the branch to allocate new skb is taken. This triggers fragmentation and computation of fraggap = skb_prev->len - maxfraglen. Fraggap can exceed MTU, causing copy = datalen - transhdrlen - fraggap to become negative. Subsequently skb_copy_and_csum_bits() writes out-of-bounds. A similar issue is present in IPv6 code. The bug was introduced in e89e9cf539a2 ("[IPv4/IPv6]: UFO Scatter-gather approach") on Oct 18 2005.
CVSS Score and Metrics +CVSS Score and Metrics -CVSS V3 Severity: | CVSS V2 Severity: |
CVSS Score : 7.0 | CVSS Score : 6.9 |
Exploit Score: 1.0 | Exploit Score: 3.4 |
Impact Score: 5.9 | Impact Score: 10.0 |
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CVSS V3 Metrics: | CVSS V2 Metrics: |
Attack Vector: LOCAL | Access Vector: LOCAL |
Attack Complexity: HIGH | Access Complexity: MEDIUM |
Privileges Required: LOW | Authentication: NONE |
User Interaction: NONE | Confidentiality: COMPLETE |
Scope: UNCHANGED | Integrity: COMPLETE |
Confidentiality: HIGH | Availability: COMPLETE |
Integrity: HIGH | |
Availability: HIGH | |
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