Malicious PDF — malware analysis report

Static analysis result for SHA-256 8571b89cf6ea0aed…

MALICIOUS

PDF

95.2 KB Created: 2021-07-07 00:35:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1cec2a42106e92b124a36544101c1d81 SHA-1: 213c105326c70960aef8511fdda80d1ee21be835 SHA-256: 8571b89cf6ea0aed2896bf0870f654174688d0d08a70d15db45e5d12e3ccb4c6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. ClamAV and ML classifiers flagged this PDF as malicious, specifically as a phishing trojan. The presence of external URIs and link farm heuristics strongly suggests an attempt to lure users to malicious or compromised content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://zpb-maciejewski.pl/upload/fck/file/pobiwinuraz.pdf
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/5a3c6584a1af9c959419923aeaab6f3a/68095839565.pdf
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/jjjpo03ri5r7ial1neqjboudb1/nixavaxexebovovosew.pdf
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/1273167beed2664d9ac4392d98406aec/redefewezokufok.pdf
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a992a610584---zexuwunenibum.pdf
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/f4uc13ras8fkfk3edvk2cqrg94/tazebuj.pdf
    • http://trans-serwis.com/userfiles/file/sariropowiz.pdf
    • http://af.ssla.ru/images/fornews/files/96051429452.pdf
    • http://macabrey-luthier.fr/data/Files/vipaboxemutatebi.pdf
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/16076b35d89089---22759077715.pdf
    • https://wulf-sanitaer.de/wp-content/plugins/super-forms/uploads/php/files/9s5o91s180l3i75tca76hu829b/88545986572.pdf
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b483063771e---18049513614.pdf
    • http://edgecs.net/documents/wezupozedivupufuvutis.pdf
    • https://traveletrust.com/basefile/traveletrustcom/files/25926718881.pdf
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c5809205f8---pefitoraf.pdf
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bec12b17293---xomowubidofiw.pdf
    • http://asiancfea.org/userfiles/file/tikevenokukutob.pdf
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/7c80aa9317fa75937378c2c5108a65dc/veridorosoti.pdf
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b055ed9f380---88426744740.pdf
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e4fe8699d3---wijixuzusenip.pdf
    • https://efnnma.org/files/file/zexifona.pdf
    • https://progin.ch/ckfinder/userfiles/files/28522941304.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=section+3+of+child+labour+prohibition+and+regulation+act+1986
    • http://irodori.kir.jp/files/file/86578965076.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_off00010ca6.bin
5672230be448c97b08b344c78f58664c1591bb4be39c6232c3ba853676d7bcc0
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CA6 11816 bytes
font_01_sfnt_off00012862.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12862 16792 bytes
font_02_sfnt_off00014074.bin
eda81a0651e3388f47fd649f1687a3474fc629c7d06d0197e6552cec4e9c791a
pdf-font-stream PDF embedded font (sfnt) at offset 0x14074 17560 bytes