Malicious PDF — malware analysis report

Static analysis result for SHA-256 7598cafb63434bd5…

MALICIOUS

PDF

80.0 KB Created: 2021-09-07 14:35:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: fb2425ff56d39d2904ca093a7d45b203 SHA-1: 3c68daf7b45eaa7081ec1565d9d12cad21f2abbd SHA-256: 7598cafb63434bd56743e15eb9d11aab696024e4a019792af98e66f4b89402ef
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample exhibits characteristics of a malicious PDF, including malformed streams and a high ML classifier score, leading to a critical ClamAV detection. It contains numerous external URIs and embedded links, many pointing to compromised CMS uploads or disposable hosting, suggesting an attempt to redirect users to malicious sites. The PDF's structure and embedded links indicate it's designed to facilitate phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7278

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://synerhu.ru/uplcv?utm_term=acura+mdx+2008+repair+manual PDF link annotation
    • http://krajinar.cz/soubory/files/xakagewoxile.pdfIn PDF document text
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/90ceb01054459667cf1ce99a811c9721/zurixabedobi.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/096204bc63ce53b69b04f05e28d9999b/gifowomigadajizilub.pdfIn PDF document text
    • http://wmc21.com/ckupload/files/3797616901.pdfIn PDF document text
    • https://www.comperat-89.fr/ckfinder/userfiles/files/zufat.pdfIn PDF document text
    • http://berkeleyhigh64.com/clients/9/99/99a482d4bd0dc5522cc24ea7f8204a07/File/37270063911.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612b5a1dbae58---5697148384.pdfIn PDF document text
    • https://austarpharma.com/upload/files/zogunedaferep.pdfIn PDF document text
    • http://longearedhounds.com/clients/65743/File/bovujexurujamapaden.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/0ps6tr3clvbedik6nfbectd082/38209448398.pdfIn PDF document text
    • http://xahscw.com/userfiles/file/fopemididev.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1917d9c203---81579964877.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/12d769951dbef22d54d3d6ccb95411cd/47548764704.pdfIn PDF document text
    • http://duszek-lasu.pl/userfiles/file/wegumanupovadigad.pdfIn PDF document text
    • http://uspeh-kursk.ru/ckfinder/userfiles/files/zimukuwuzoxofizud.pdfIn PDF document text
    • http://www.childofafrica.org/media/userfiles/file/69497319867.pdfIn PDF document text
    • https://advance-pack.com/editor_upload/file/48794801877.pdfIn PDF document text
    • http://ciskmv.com/css/file/rukefabimet.pdfIn PDF document text
    • http://chi-kara.net/Upload/files/1118796837.pdfIn PDF document text
    • https://abeess.com/userfiles/file/xikezokipalap.pdfIn PDF document text
    • https://clumba-indoor.ru/files/files/sepilad.pdfIn PDF document text
    • https://anukulagrotech.com/userfiles/file/10675295675.pdfIn PDF document text
    • http://xboxheerlen.nl/userfiles/file/90750680514.pdfIn PDF document text
    • https://www.letspassdriving.co.uk/wp-content/plugins/super-forms/uploads/php/files/tuonf5ai6orefremd0frag7ma1/46351811322.pdfIn PDF document text
    • https://behagi.eus/files/galeria/files/33041229276.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001002e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1002E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011845.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11845 10924 bytes
SHA-256: 76159c55db2327e696802ab61a64f6b65b617141614df670e9ac6c683f945ac7