Re: Cygwin setup error

[Brian Inglis <Brian.Inglis@SystematicSw.ab.ca>]

On 2020-04-21 12:33, Marco Atzeri via Cygwin wrote:
> Am 21.04.2020 um 18:08 schrieb Antonio Cesar Rosa:
>> I do not think so. See the output from Virustotal:
>> 2431de4597a2162f3e1d60af90f638b41677265b07cc66fcb0231fdde452c841
>> setup-x86_64.exe 1.29 MB 2020-04-21 00:31:19 UTC
>> Size
>> 15 hours ago
>> 64bits direct-cpu-clock-access overlay peexe runtime-modules
>> DETECTION DETAILS BEHAVIOR COMMUNITY
>> SecureAge APEX Malicious MaxSecure Trojan.Malware.300983.susgen
>> Lastline MALWARE Acronis Undetected

Scoring 2[.5]/71 is not exactly a threatening consensus - believe the 69 and
ignore the 2[.5].
The URL check has eight more checkers excluding the three false positives score
0/80.
Many AVs use "heuristic/WAG" approaches which often give false positives on
installers.
This group probably sees about one false positive a month, but I don't ever
recall a real issue in about/over ten years.

> please reply on mailing list in copy.
> Virus Total with the URL https://cygwin.com/setup-x86_64.exe
> gives all clean.
> If you have a different result. likely you have a tampered file.
> And using the signature available on
> https://cygwin.com/install.html
> we also have:
> $ gpg2 --verify setup-x86_64.exe.sig
> gpg: assuming signed data in 'setup-x86_64.exe'
> gpg: Signature made Sat, Mar 21, 2020  6:35:25 PM CET
> gpg:                using DSA key 1169DF9F22734F743AA59232A9A262FF676041BA
> gpg: checking the trustdb
> gpg: marginals needed: 3  completes needed: 1  trust model: pgp
> gpg: depth: 0  valid:   1  signed:   1  trust: 0-, 0q, 0n, 0m, 0f, 1u
> gpg: depth: 1  valid:   1  signed:   0  trust: 1-, 0q, 0n, 0m, 0f, 0u
> gpg: next trustdb check due at 2022-02-26
> gpg: Good signature from "Cygwin <cygwin@cygwin.com>" [ultimate]
> gpg: Signature made Sat, Mar 21, 2020  6:35:25 PM CET
> gpg:                using RSA key 56405CF6FCC81574682A5D561A698DE9E2E56300
> gpg: Good signature from "Cygwin <cygwin@cygwin.com>" [full]

$ TZ=UTC wget -N http://cygwin.com/setup-x86{_64,}.exe{.sig,}
2020-04-21 21:26:37 URL:http://cygwin.com/setup-x86_64.exe.sig [661/661] ->
"setup-x86_64.exe.sig" [1]
2020-04-21 21:26:38 URL:http://cygwin.com/setup-x86_64.exe [1352723/1352723] ->
"setup-x86_64.exe" [1]
2020-04-21 21:26:38 URL:http://cygwin.com/setup-x86.exe.sig [661/661] ->
"setup-x86.exe.sig" [1]
2020-04-21 21:26:41 URL:http://cygwin.com/setup-x86.exe [1248787/1248787] ->
"setup-x86.exe" [1]
FINISHED --2020-04-21 21:26:41--
Total wall clock time: 4.4s
Downloaded: 4 files, 2.5M in 2.2s (1.12 MB/s)
$ TZ=UTC ls -glo --full setup-x86{_64,}.exe{.sig,}
-rw-r--r--+ 1 1248787 2020-03-21 17:28:48.000000000 +0000 setup-x86.exe
-rw-r--r--+ 1     661 2020-03-21 17:29:04.000000000 +0000 setup-x86.exe.sig
-rw-r--r--+ 1 1352723 2020-03-21 17:35:04.000000000 +0000 setup-x86_64.exe
-rw-r--r--+ 1     661 2020-03-21 17:35:25.000000000 +0000 setup-x86_64.exe.sig
$ TZ=UTC sha256sum setup-x86{_64,}.exe{.sig,}
9e99b618cf6cf0e7a6efac9bff2028acebdb44fd552407e4cb7839f0867b035e
*setup-x86_64.exe.sig
2431de4597a2162f3e1d60af90f638b41677265b07cc66fcb0231fdde452c841 *setup-x86_64.exe
c7b45a34a0ef18b409a385c7157fd7bb68a799148c212bab74037e0438f5addb *setup-x86.exe.sig
d218a41a45fcec581affd0e1ccc66011aa06a3a9b299576104546074e8480064 *setup-x86.exe
$ TZ=UTC gpg2 --verify setup-x86_64.exe{.sig,}
gpg: Signature made 2020 Mar 21 Sat 17:35:25 UTC
gpg:                using DSA key 1169DF9F22734F743AA59232A9A262FF676041BA
gpg: Good signature from "Cygwin <cygwin@cygwin.com>" [full]
gpg: Signature made 2020 Mar 21 Sat 17:35:25 UTC
gpg:                using RSA key 56405CF6FCC81574682A5D561A698DE9E2E56300
gpg: Good signature from "Cygwin <cygwin@cygwin.com>" [full]
$ TZ=UTC gpg2 --verify setup-x86.exe{.sig,}
gpg: Signature made 2020 Mar 21 Sat 17:29:04 UTC
gpg:                using DSA key 1169DF9F22734F743AA59232A9A262FF676041BA
gpg: Good signature from "Cygwin <cygwin@cygwin.com>" [full]
gpg: Signature made 2020 Mar 21 Sat 17:29:04 UTC
gpg:                using RSA key 56405CF6FCC81574682A5D561A698DE9E2E56300
gpg: Good signature from "Cygwin <cygwin@cygwin.com>" [full]

Same files from a month ago with same digests and signatures.
Many have downloaded and used it in that timeframe for dozens of package
installs and upgrades with no issues or reports before yours.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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