CVE-2022-3252
SwiftNIO Extras vulnerable to improper detection of complete HTTP body decompression
Improper detection of complete HTTP body decompression SwiftNIO Extras provides a pair of helpers for transparently decompressing received HTTP request or response bodies. These two objects (HTTPRequestDecompressor and HTTPResponseDecompressor) both failed to detect when the decompressed body was considered complete. If trailing junk data was appended to the HTTP message body, the code would repeatedly attempt to decompress this data and fail. This would lead to an infinite loop making no forward progress, leading to livelock of the system and denial-of-service. This issue can be triggered by any attacker capable of sending a compressed HTTP message. Most commonly this is HTTP servers, as compressed HTTP messages cannot be negotiated for HTTP requests, but it is possible that users have configured decompression for HTTP requests as well. The attack is low effort, and likely to be reached without requiring any privilege or system access. The impact on availability is high: the process immediately becomes unavailable but does not immediately crash, meaning that it is possible for the process to remain in this state until an administrator intervenes or an automated circuit breaker fires. If left unchecked this issue will very slowly exhaust memory resources due to repeated buffer allocation, but the buffers are not written to and so it is possible that the processes will not terminate for quite some time. This risk can be mitigated by removing transparent HTTP message decompression. The issue is fixed by correctly detecting the termination of the compressed body as reported by zlib and refusing to decompress further data. The issue was found by Vojtech Rylko (https://github.com/vojtarylko) and reported publicly on GitHub.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
7.5
Improper detection of complete HTTP body decompression SwiftNIO Extras provides a pair of helpers for transparently decompressing received HTTP request or response bodies. These two objects (HTTPRequestDecompressor and HTTPResponseDecompressor) both failed to detect when the decompressed body was considered complete. If trailing junk data was appended to the HTTP message body, the code would repeatedly attempt to decompress this data and fail. This would lead to an infinite loop making no forward progress, leading to livelock of the system and denial-of-service. This issue can be triggered by any attacker capable of sending a compressed HTTP message. Most commonly this is HTTP servers, as compressed HTTP messages cannot be negotiated for HTTP requests, but it is possible that users have configured decompression for HTTP requests as well. The attack is low effort, and likely to be reached without requiring any privilege or system access. The impact on availability is high: the process immediately becomes unavailable but does not immediately crash, meaning that it is possible for the process to remain in this state until an administrator intervenes or an automated circuit breaker fires. If left unchecked this issue will very slowly exhaust memory resources due to repeated buffer allocation, but the buffers are not written to and so it is possible that the processes will not terminate for quite some time. This risk can be mitigated by removing transparent HTTP message decompression. The issue is fixed by correctly detecting the termination of the compressed body as reported by zlib and refusing to decompress further data. The issue was found by Vojtech Rylko (https://github.com/vojtarylko) and reported publicly on GitHub.
- Record
CVE-2022-3252- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-606, CWE-835
- Updated
- 2026-11-02
CVE List No score
Improper detection of complete HTTP body decompression SwiftNIO Extras provides a pair of helpers for transparently decompressing received HTTP request or response bodies. These two objects (HTTPRequestDecompressor and HTTPResponseDecompressor) both failed to detect when the decompressed body was considered complete. If trailing junk data was appended to the HTTP message body, the code would repeatedly attempt to decompress this data and fail. This would lead to an infinite loop making no forward progress, leading to livelock of the system and denial-of-service. This issue can be triggered by any attacker capable of sending a compressed HTTP message. Most commonly this is HTTP servers, as compressed HTTP messages cannot be negotiated for HTTP requests, but it is possible that users have configured decompression for HTTP requests as well. The attack is low effort, and likely to be reached without requiring any privilege or system access. The impact on availability is high: the process immediately becomes unavailable but does not immediately crash, meaning that it is possible for the process to remain in this state until an administrator intervenes or an automated circuit breaker fires. If left unchecked this issue will very slowly exhaust memory resources due to repeated buffer allocation, but the buffers are not written to and so it is possible that the processes will not terminate for quite some time. This risk can be mitigated by removing transparent HTTP message decompression. The issue is fixed by correctly detecting the termination of the compressed body as reported by zlib and refusing to decompress further data. The issue was found by Vojtech Rylko (https://github.com/vojtarylko) and reported publicly on GitHub.
- Record
CVE-2022-3252- Weakness
- CWE-606
- Updated
- 2026-11-02
EUVDEUVD-2023-1722 No score
Improper detection of complete HTTP body decompression SwiftNIO Extras provides a pair of helpers for transparently decompressing received HTTP request or response bodies. These two objects (HTTPRequestDecompressor and HTTPResponseDecompressor) both failed to detect when the decompressed body was considered complete. If trailing junk data was appended to the HTTP message body, the code would repeatedly attempt to decompress this data and fail. This would lead to an infinite loop making no forward progress, leading to livelock of the system and denial-of-service. This issue can be triggered by any attacker capable of sending a compressed HTTP message. Most commonly this is HTTP servers, as compressed HTTP messages cannot be negotiated for HTTP requests, but it is possible that users have configured decompression for HTTP requests as well. The attack is low effort, and likely to be reached without requiring any privilege or system access. The impact on availability is high: the process immediately becomes unavailable but does not immediately crash, meaning that it is possible for the process to remain in this state until an administrator intervenes or an automated circuit breaker fires. If left unchecked this issue will very slowly exhaust memory resources due to repeated buffer allocation, but the buffers are not written to and so it is possible that the processes will not terminate for quite some time. This risk can be mitigated by removing transparent HTTP message decompression. The issue is fixed by correctly detecting the termination of the compressed body as reported by zlib and refusing to decompress further data. The issue was found by Vojtech Rylko (https://github.com/vojtarylko) and reported publicly on GitHub.
- Record
EUVD-2023-1722- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-773g-x274-8qmf
7.5
SwiftNIO Extras vulnerable to improper detection of complete HTTP body decompression
SwiftNIO Extras provides a pair of helpers for transparently decompressing received HTTP request or response bodies. These two objects (HTTPRequestDecompressor and HTTPResponseDecompressor) both failed to detect when the decompressed body was considered complete. If trailing junk data was appended to the HTTP message body, the code would repeatedly attempt to decompress this data and fail. This would lead to an infinite loop making no forward progress, leading to livelock of the system and denial-of-service.
This issue can be triggered by any attacker capable of sending a compressed HTTP message. Most commonly this is HTTP servers, as compressed HTTP messages cannot be negotiated for HTTP requests, but it is possible that users have configured decompression for HTTP requests as well. The attack is low effort, and likely to be reached without requiring any privilege or system access. The impact on availability is high: the process immediately becomes unavailable but does not immediately crash, meaning that it is possible for the process to remain in this state until an administrator intervenes or an automated circuit breaker fires. If left unchecked this issue will very slowly exhaust memory resources due to repeated buffer allocation, but the buffers are not written to and so it is possible that the processes will not terminate for quite some time.
This risk can be mitigated by removing transparent HTTP message decompression. The issue is fixed by correctly detecting the termination of the compressed body as reported by zlib and refusing to decompress further data.
- Record
GHSA-773g-x274-8qmf- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-835
- Updated
- 2026-11-02
OSVGHSA-773g-x274-8qmf
7.5
SwiftNIO Extras vulnerable to improper detection of complete HTTP body decompression
SwiftNIO Extras provides a pair of helpers for transparently decompressing received HTTP request or response bodies. These two objects (HTTPRequestDecompressor and HTTPResponseDecompressor) both failed to detect when the decompressed body was considered complete. If trailing junk data was appended to the HTTP message body, the code would repeatedly attempt to decompress this data and fail. This would lead to an infinite loop making no forward progress, leading to livelock of the system and denial-of-service.
This issue can be triggered by any attacker capable of sending a compressed HTTP message. Most commonly this is HTTP servers, as compressed HTTP messages cannot be negotiated for HTTP requests, but it is possible that users have configured decompression for HTTP requests as well. The attack is low effort, and likely to be reached without requiring any privilege or system access. The impact on availability is high: the process immediately becomes unavailable but does not immediately crash, meaning that it is possible for the process to remain in this state until an administrator intervenes or an automated circuit breaker fires. If left unchecked this issue will very slowly exhaust memory resources due to repeated buffer allocation, but the buffers are not written to and so it is possible that the processes will not terminate for quite some time.
This risk can be mitigated by removing transparent HTTP message decompression. The issue is fixed by correctly detecting the termination of the compressed body as reported by zlib and refusing to decompress further data.
- Record
GHSA-773g-x274-8qmf- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-835
- Updated
- 2026-11-02
OSV No score
Improper detection of complete HTTP body decompression SwiftNIO Extras provides a pair of helpers for transparently decompressing received HTTP request or response bodies. These two objects (HTTPRequestDecompressor and HTTPResponseDecompressor) both failed to detect when the decompressed body was considered complete. If trailing junk data was appended to the HTTP message body, the code would repeatedly attempt to decompress this data and fail. This would lead to an infinite loop making no forward progress, leading to livelock of the system and denial-of-service. This issue can be triggered by any attacker capable of sending a compressed HTTP message. Most commonly this is HTTP servers, as compressed HTTP messages cannot be negotiated for HTTP requests, but it is possible that users have configured decompression for HTTP requests as well. The attack is low effort, and likely to be reached without requiring any privilege or system access. The impact on availability is high: the process immediately becomes unavailable but does not immediately crash, meaning that it is possible for the process to remain in this state until an administrator intervenes or an automated circuit breaker fires. If left unchecked this issue will very slowly exhaust memory resources due to repeated buffer allocation, but the buffers are not written to and so it is possible that the processes will not terminate for quite some time. This risk can be mitigated by removing transparent HTTP message decompression. The issue is fixed by correctly detecting the termination of the compressed body as reported by zlib and refusing to decompress further data. The issue was found by Vojtech Rylko (https://github.com/vojtarylko) and reported publicly on GitHub.
- Record
CVE-2022-3252- Weakness
- CWE-606
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
github.com/apple/swift-nio-extrasSwiftURL |
1.11.0 up to 1.14.0 | 1.14.0 |
github.com/apple/swift-nio-extrasSwiftURL |
1.10.0 up to 1.10.3 | 1.10.3 |
github.com/apple/swift-nio-extrasSwiftURL |
before 1.9.2 | 1.9.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2022-3252 is a high vulnerability (CVSS 7.5) in Swift Project Swiftnio Extras, published September 21, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.83%, the 57th percentile. Fixed in github.com/apple/swift-nio-extras 1.14.0.
References
github.com/apple/swift-nio-extras/security/advisories/GHSA-773g-x274-8qmf
nvd.nist.gov/vuln/detail/CVE-2022-3252
github.com/apple/swift-nio-extras/pull/177
github.com/apple/swift-nio-extras/pull/177/commits/359015de2c49e426c27b1d25dbf599b08a9d3ee6
github.com/advisories/GHSA-773g-x274-8qmf
github.com/CVEProject/cvelistV5/tree/main/cves/2022/3xxx/CVE-2022-3252.json
github.com/apple/swift-nio-extras