Malicious PDF — malware analysis report

Static analysis result for SHA-256 426aa0d6e5ecf665…

MALICIOUS

PDF

88.7 KB Created: 2021-07-26 17:51:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 866c9075c89cfdaf495b48b1bc2afeb1 SHA-1: 8d34b17bd7fdd84b4a733241b5371cca38d6d2c7 SHA-256: 426aa0d6e5ecf665d96c51c9828d88e0c2b01142367c7ca939a7aec2013a3b10
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to compromised CMS upload directories, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a malicious document, likely leveraging embedded JavaScript for redirection or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076b2fbef4bc.pdf
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/b0bc7462a9a398a5467385f19238d75a/rixilafuruzekeri.pdf
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f306263384---litixoxokasowokaf.pdf
    • http://dansensvenner.dk/imagesfile///19956988924.pdf
    • https://billionbosses.com/ckfinder/userfiles/files/57129368385.pdf
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609e1c9e91be1---49205497122.pdf
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/86200530567.pdf
    • https://ludifrance.fr/userfiles/file/worajisutek.pdf
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/p4728pr67lfigqu6f1tt1ipbv1/pomuk.pdf
    • http://files.ibiza-ferien.de/file/82775781647.pdf
    • https://lecormier-menuiserie.com/www/upload/files/41628821977.pdf
    • http://ddservice-bmw.pl/userfiles/file/xidipevaxusisixozogojor.pdf
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/fa1197b181d5aa64b7a67427024815b3/gufegenavijemituvedupe.pdf
    • https://eletvital.hu/uploads/files/22012285562.pdf
    • https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/23ef6ee73857c5760ff77cb1cccc850c/somazugi.pdf
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/3cotcrihbubsv461l4th2g27ah/1007844074.pdf
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16073492e8e5b4---25453742346.pdf
    • https://universal4shipping.net/userfiles/file/39523597411.pdf
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606c96febec3d---88209129618.pdf
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160d5455d8ce56---34893081691.pdf
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609f7caa5fca2---vapikewukuzewopidubad.pdf
    • https://gastriklandsbf.se/UserFiles/files/91957007534.pdf
    • http://bhs1966maui.com/clients/64750/File/mujoburezomeridokusup.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=can+pneumonia+cause+pulmonary+oedema
    • 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_off0000f71a.bin
ec814392d89455f99fbaef991778539e9e5fcc755eea8c1beda98545bde03386
pdf-font-stream PDF embedded font (sfnt) at offset 0xF71A 17020 bytes
font_01_sfnt_off000123ae.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x123AE 16792 bytes
font_02_sfnt_off00013bc5.bin
bf3f05d6d73d13f9993c6e58d1afc16a5031c96716dcfd5b0d32d95d35b49f1a
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BC5 10820 bytes