Malicious PDF — malware analysis report

Static analysis result for SHA-256 27c77f7f1fa2e4cc…

MALICIOUS

PDF

79.4 KB Created: 2021-09-16 09:33:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 944bd5352b8ba02e7382e5c007a1da10 SHA-1: b914ae207b8e877bdef48fc442c67ddca830df59 SHA-256: 27c77f7f1fa2e4cc895e7b9ee810d08dce15a9852fbf950572bd36ddc464bbeb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, with numerous URLs pointing to compromised WordPress sites. These links likely serve as a lure to redirect users to malicious or phishing content, aligning with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe6e6c22ef---vepokavasevus.pdf
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161427a40f0e04---61054524468.pdf
    • http://maquinandoysubastando.com/dleyes/admin/fotos/file/wuwuwegofovoripi.pdf
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/6daf6f320a14ffec994dbabd2c0f08f1/lijexiwixopem.pdf
    • http://allineers.netlovestories.com/upload/files/venafonelaluvobirubikap.pdf
    • http://clinivetmadonnadirosa.eu/userfiles/files/34485759503.pdf
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/eu8meladssdg2lqgmuo00kge85/40722530590.pdf
    • https://10fci.org/userfiles/file/71462896613.pdf
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a620e1f46e---mirepijifilexuxog.pdf
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/161394cca3c694---32128652207.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/161365c9143ccf---10066018874.pdf
    • https://organicfertilizerproduction.com/d/files/zixivofonaxuxev.pdf
    • http://be-now.pl/userfiles/file/63236568595.pdf
    • https://blv.by/upload/editor/files/fuforigitewanizinin.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140bac129b59---jipiserapugixusosadi.pdf
    • http://kiddeefire.com/media/userfiles/files/53891611577.pdf
    • https://hinodanang.com/uploads/image/files/33982837705.pdf
    • http://ng-sons.com/userfiles/file/66595450785.pdf
    • https://thefertilizerequipment.com/d/files/89478155951.pdf
    • http://hebakotb.net/userfiles/file/bunaxugededuvisot.pdf
    • https://aawyx.com/sites/default/imageuser/file/84704630742.pdf
    • https://allora-tour.by/var/upload/file/63197787957.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=galaxian+for+android
    • 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_off0000d541.bin
3a08455c93bf2ba73c71163615f7003b03d8fc8839ad5b7931b674311bb7e674
pdf-font-stream PDF embedded font (sfnt) at offset 0xD541 16940 bytes
font_01_sfnt_off00010190.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10190 16792 bytes
font_02_sfnt_off000119a7.bin
1e4225b456d7c0530a22c09d7dfef76495c59ec31a8080dddb5a9f9871812c9a
pdf-font-stream PDF embedded font (sfnt) at offset 0x119A7 10092 bytes