Answer in brief
CVE-2021-47397 records a High severity (CVSS 7.5) vulnerability in sctp: break out if skb_header_pointer returns NULL in sctp_rcv_ootb. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2021-47397 records a High severity (CVSS 7.5) vulnerability in sctp: break out if skb_header_pointer returns NULL in sctp_rcv_ootb. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=3acb50c18d8d6650f10919464ade4dcdaf41d62f <77bc7dcf0fcc1519341a91788d7a2914fcfddf6d || >=3acb50c18d8d6650f10919464ade4dcdaf41d62f <8c630a7b4f9dec63f08bd881ab77984a724a5124 || >=3acb50c18d8d6650f10919464ade4dcdaf41d62f <ec018021cf445abbe8e2f3e2a7f1dcc813cb8ea1 || >=3acb50c18d8d6650f10919464ade4dcdaf41d62f <9c6591ae8e63f93c895ad5e2703c36c548aac997 || >=3acb50c18d8d6650f10919464ade4dcdaf41d62f <8180611c238e11676612eb2a9828b1c7a3a4d77b || >=3acb50c18d8d6650f10919464ade4dcdaf41d62f <f7e745f8e94492a8ac0b0a26e25f2b19d342918f | 77bc7dcf0fcc1519341a91788d7a2914fcfddf6d, 8c630a7b4f9dec63f08bd881ab77984a724a5124, ec018021cf445abbe8e2f3e2a7f1dcc813cb8ea1, 9c6591ae8e63f93c895ad5e2703c36c548aac997, 8180611c238e11676612eb2a9828b1c7a3a4d77b, f7e745f8e94492a8ac0b0a26e25f2b19d342918f |
| Linux/Linuxgeneric | 4.8 | Not reported |
Published upstream
May 21, 2024
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 4, 2026
In the Linux kernel, the following vulnerability has been resolved: sctp: break out if skb_header_pointer returns NULL in sctp_rcv_ootb We should always check if skb_header_pointer's return is NULL before using it, otherwise it may cause null-ptr-deref, as syzbot reported: KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:sctp_rcv_ootb net/sctp/input.c:705 [inline] RIP: 0010:sctp_rcv+0x1d84/0x3220 net/sctp/input.c:196 Call Trace: <IRQ> sctp6_rcv+0x38/0x60 net/sctp/ipv6.c:1109 ip6_protocol_deliver_rcu+0x2e9/0x1ca0 net/ipv6/ip6_input.c:422 ip6_input_finish+0x62/0x170 net/ipv6/ip6_input.c:463 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip6_input+0x9c/0xd0 net/ipv6/ip6_input.c:472 dst_input include/net/dst.h:460 [inline] ip6_rcv_finish net/ipv6/ip6_input.c:76 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ipv6_rcv+0x28c/0x3c0 net/ipv6/ip6_input.c:297
Quoted source text, attributed separately from HOL analysis.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=3acb50c18d8d6650f10919464ade4dcdaf41d62f <77bc7dcf0fcc1519341a91788d7a2914fcfddf6d || >=3acb50c18d8d6650f10919464ade4dcdaf41d62f <8c630a7b4f9dec63f08bd881ab77984a724a5124 || >=3acb50c18d8d6650f10919464ade4dcdaf41d62f <ec018021cf445abbe8e2f3e2a7f1dcc813cb8ea1 || >=3acb50c18d8d6650f10919464ade4dcdaf41d62f <9c6591ae8e63f93c895ad5e2703c36c548aac997 || >=3acb50c18d8d6650f10919464ade4dcdaf41d62f <8180611c238e11676612eb2a9828b1c7a3a4d77b || >=3acb50c18d8d6650f10919464ade4dcdaf41d62f <f7e745f8e94492a8ac0b0a26e25f2b19d342918f | 77bc7dcf0fcc1519341a91788d7a2914fcfddf6d, 8c630a7b4f9dec63f08bd881ab77984a724a5124, ec018021cf445abbe8e2f3e2a7f1dcc813cb8ea1, 9c6591ae8e63f93c895ad5e2703c36c548aac997, 8180611c238e11676612eb2a9828b1c7a3a4d77b, f7e745f8e94492a8ac0b0a26e25f2b19d342918f |
| Linux/Linuxgeneric | 4.8 | Not reported |
Published upstream
May 21, 2024
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 4, 2026
In the Linux kernel, the following vulnerability has been resolved: sctp: break out if skb_header_pointer returns NULL in sctp_rcv_ootb We should always check if skb_header_pointer's return is NULL before using it, otherwise it may cause null-ptr-deref, as syzbot reported: KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:sctp_rcv_ootb net/sctp/input.c:705 [inline] RIP: 0010:sctp_rcv+0x1d84/0x3220 net/sctp/input.c:196 Call Trace: <IRQ> sctp6_rcv+0x38/0x60 net/sctp/ipv6.c:1109 ip6_protocol_deliver_rcu+0x2e9/0x1ca0 net/ipv6/ip6_input.c:422 ip6_input_finish+0x62/0x170 net/ipv6/ip6_input.c:463 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip6_input+0x9c/0xd0 net/ipv6/ip6_input.c:472 dst_input include/net/dst.h:460 [inline] ip6_rcv_finish net/ipv6/ip6_input.c:76 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ipv6_rcv+0x28c/0x3c0 net/ipv6/ip6_input.c:297
Quoted source text, attributed separately from HOL analysis.