Malicious PDF — malware analysis report

Static analysis result for SHA-256 b29c2e91bdc71d36…

MALICIOUS

PDF

69.5 KB Created: 2021-09-24 21:44:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b9ffd978edd112cb2aaea79c9ebd5f5d SHA-1: 0843771c3e5ec9a8cc0997dfb2cc6eac2876411f SHA-256: b29c2e91bdc71d361d9be3bdfa84f74816a577577c5761a2c04f19fb48f1e087
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs and link farms pointing to external sites, suggesting it's used to redirect users to potentially malicious content or phishing pages. The presence of PDF-specific heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://krisoc.ru/uplcv?utm_term=app+where+i+can+download+movies
    • http://momsystem.ru/public/file/72503779434.pdf
    • https://vietnamwelder.vn/uploads/news_file/nibufotevurupuzavu.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613eea4db5b50---voduwonejod.pdf
    • http://373113.linker.tw/files/salasotiboxiditubutif.pdf
    • http://jumpinfit.it/userfiles/files/wanogutiwekazaluvoworef.pdf
    • http://geose.ru/userfiles/file/81765894056.pdf
    • https://108pizza.pl/uploads/userfiles/files/gedewerowe.pdf
    • https://g4m3s-4p1-12s1.com/contents/files/26055457173.pdf
    • https://shunnasato.com/68915132070.pdf
    • http://fotografoenricogiampieri.it/userfiles/files/satuva.pdf
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/1613a4605e7584---vajogujibedema.pdf
    • http://nwatchonline.net/userfiles/file/75344794414.pdf
    • https://bharatiyabhashaparishad.org/ckfinder/userfiles/files/26010616528.pdf
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/4712180199.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/a85a139e7080c2997b0cacf2d5ead940/gosilexegozizifoxifemax.pdf
    • http://locum-system.pl/userfiles/file/dapebukukizid.pdf
    • http://bagliodeimille.it/userfiles/files/wakasukezuxabumun.pdf
    • http://vonschickenconcord.com/uploads/files/vifodofurefukoz.pdf
    • https://seerupit.dk/assens/file/noliv.pdf
    • https://butyfarm.mm520.net/userfiles/files/pozisuxagodolojiwok.pdf
    • http://ottomaniantextile.com/userfiles/file/89657008377.pdf
    • https://delcinfo.ru/img/files/files/milijuwilobikajepas.pdf
    • http://zs-oilfieldequip.ru/d/files/xexejevasiwewaduwitupeses.pdf
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e28631d2fc---73848030964.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b19e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB19E 16792 bytes
font_01_sfnt_off0000c9b5.bin
dcc3bde4e5c3e52d6d76bead155da34bad683c3d61d146559477d7d42c172bd3
pdf-font-stream PDF embedded font (sfnt) at offset 0xC9B5 10816 bytes
font_02_sfnt_off0000e282.bin
056bf6b0850ad4e917a2850d23255606236701dffef8acf78e93160e7fc8b053
pdf-font-stream PDF embedded font (sfnt) at offset 0xE282 14912 bytes