High
erlang-cowlib — security advisory
Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in ninenines cowlib allows unauthenticated remote denial of service via memory exhaustion. cow_spdy:inflate/2 in cowlib passes peer-supplied compressed bytes directly to zlib:inflate/2 with no output size bound. The SPDY header compression dictionary (?ZDICT) is public, and zlib compresses long runs of repeated bytes at roughly 1024:1, so a few kilobytes of SPDY frame payload can decompress to gigabytes on the BEAM heap, OOM-killing the node. A single unauthenticated SPDY frame is sufficient to trigger the condition. The parsers for syn_stream, syn_reply, and headers frame types are all affected via cow_spdy:parse_headers/2. This issue affects cowlib from 0.1.0 before 2.16.1.
- Products
- erlang-cowlib
- Affected versions
- 1.3.0-1, 1.3.0-2, 1.3.0-3, 1.3.0-3build1, 2.19.0-1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-43970
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:12 UTC · Revision 1
Source evidence
Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in ninenines cowlib allows unauthenticated remote denial of service via memory exhaustion. cow_spdy:inflate/2 in cowlib passes peer-supplied compressed bytes directly to zlib:inflate/2 with no output size bound. The SPDY header compression dictionary (?ZDICT) is public, and zlib compresses long runs of repeated bytes at roughly 1024:1, so a few kilobytes of SPDY frame payload can decompress to gigabytes on the BEAM heap, OOM-killing the node. A single unauthenticated SPDY frame is sufficient to trigger the condition. The parsers for syn_stream, syn_reply, and headers frame types are all affected via cow_spdy:parse_headers/2. This issue affects cowlib from 0.1.0 before 2.16.1.
osv:UBUNTU-CVE-2026-43970
erlang-cowlib
Fixed versions: Not specified
erlang-cowlib
Fixed versions: Not specified
erlang-cowlib
Fixed versions: Not specified
erlang-cowlib
Fixed versions: Not specified
erlang-cowlib
Fixed versions: Not specified
erlang-cowlib
Fixed versions: Not specified
erlang-cowlib
Fixed versions: Not specified
erlang-cowlib
Fixed versions: Not specified
Complete source record
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