Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9248c5e700f5931…

MALICIOUS

PDF

85.7 KB Created: 2021-06-26 02:51:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b21a003970e073c170afbdf7163d4976 SHA-1: 0234b6679cc3daf804153afd51866ed2a14abbd7 SHA-256: a9248c5e700f5931a41a791cebe05ea29a52d66cf793ca1a10b68e884b5d6d15
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It contains numerous links pointing to compromised CMS upload directories, suggesting it's designed to lure users to malicious sites. The document body is heavily obfuscated and unreadable, providing no direct user-facing content, but the heuristic firings strongly indicate a link farm used for malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/5c8696dbb46f9bbb1787c5a5f9aa46ef/jemuxetugezalafuwejunu.pdf
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad4d6805671---bibokududuxidolobub.pdf
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160ac58c29724e---55628685604.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a3790f82e2d---44675575088.pdf
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1607943592d3ee---lezatoj.pdf
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/bm86skvjobsp3cljhp7fu3a4c6/27944265949.pdf
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b51cc6b54---xedirotalimimoga.pdf
    • http://am-assets.com/aom/magnolia/userfiles/file/segulisog.pdf
    • http://baybayankaauamo.com/clients/c/c9/c9e0f772d4a556598cfa564a27137582/File/70003447627.pdf
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b478974a5bd---nexufulonuxasosus.pdf
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c6fc413e4ce---24192195524.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607086abbec66---pitupalefaru.pdf
    • http://naasschoolofmotoring.ie/fckeditor/userfiles/file/65937006120.pdf
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/0re43bhdkf77r1hi1tj32jhdkh/52453139851.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc39b804e4---fiwupitefezekesodep.pdf
    • https://trimix.bg/UserFiles/File/28813112639.pdf
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087581d74543---49073310868.pdf
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076161e44b90---60736240636.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=sympathy+in+a+sentence
    • 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_off0000ed34.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED34 16792 bytes
font_01_sfnt_off00010546.bin
88256ce39ea4051dc23512afb5b25101c30f69459388e4cd4e9ec8db1ecb122e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10546 17208 bytes
font_02_sfnt_off00013240.bin
aff6cb7e7943e65fec10a2b6ee24257ce29606addf7ccab8cd3c4ca310647c02
pdf-font-stream PDF embedded font (sfnt) at offset 0x13240 10564 bytes