CVE-2026-43970

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Source
https://cve.org/CVERecord?id=CVE-2026-43970
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-43970.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-43970
Aliases
Downstream
Published
2026-05-13T18:43:11.640Z
Modified
2026-07-08T08:13:29.452986877Z
Severity
  • 8.2 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
Decompression Bomb in cow_spdy:inflate/2 Allows Memory Exhaustion via Crafted SPDY Frame
Details

Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in ninenines cowlib allows unauthenticated remote denial of service via memory exhaustion.

cowspdy: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 synstream, synreply, and headers frame types are all affected via cowspdy:parse_headers/2.

This issue affects cowlib from 0.1.0 before 2.16.1.

Database specific 
{
    "unresolved_ranges": [
        {
            "source": "AFFECTED_FIELD",
            "extracted_events": [
                {
                    "introduced": "fad5c0049df278cc498b6cdb519b09e845a070a8"
                },
                {
                    "fixed": "16aad3fb9f81f5cda4d1706ff0c54237c619c282"
                }
            ]
        }
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43970.json",
    "cna_assigner": "EEF",
    "cwe_ids": [
        "CWE-409"
    ]
}
References

Affected packages

Git / github.com/ninenines/cowlib

Affected ranges

Type
GIT
Repo
https://github.com/ninenines/cowlib
Events
Introduced
2f35af5b0a67f591dde5ae4305a9587988a37c0c
Fixed
bae6b022af54566f3518a3aa59083b4591d552de
Fixed
16aad3fb9f81f5cda4d1706ff0c54237c619c282
Database specific 
{
    "source": [
        "DESCRIPTION",
        "REFERENCES"
    ],
    "extracted_events": [
        {
            "introduced": "0.1.0"
        },
        {
            "fixed": "2.16.1"
        }
    ]
}

Affected versions

0.*
0.1.0
0.2.0
0.3.0
0.4.0
0.5.0
0.5.1
0.6.0
0.6.1
0.6.2
1.*
1.0.0
1.0.1
1.1.0
1.2.0
1.3.0
2.*
2.0.0
2.0.0-pre.1
2.0.0-rc.1
2.0.1
2.1.0
2.10.0
2.10.1
2.11.0
2.12.0
2.12.1
2.13.0
2.14.0
2.15.0
2.16.0
2.2.0
2.2.1
2.3.0
2.4.0
2.5.0
2.5.1
2.6.0
2.7.0
2.7.1
2.7.2
2.7.3
2.8.0
2.9.0
2.9.1

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-43970.json"