Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5c7f10c69679879…

MALICIOUS

PDF

75.2 KB Created: 2021-09-18 14:09:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6120eeb68672a43981943fcf84c8320d SHA-1: c5b0ac800d592f49bba492c2d078ac5a9b173dc5 SHA-256: a5c7f10c69679879ff1ee3d4f3d8289497a7329dde156cb876e9fbbe01e70873
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised or disposable hosting, indicating a link farm designed to redirect users. Heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest malicious intent, likely for phishing or malware delivery. The ML classifier and ClamAV detection further confirm its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://crysiq.ru/uplcv?utm_term=new+shayari+2020
    • http://stamforgtechnologies.com/uploads/wowidixevobirevowal.pdf
    • http://jnejendomsdrift.dk/userfiles/file/2489899888.pdf
    • https://cortopolis.ar/userfiles/file/74260113075.pdf
    • http://giaodantanthaison.com/Images_upload/files/napelejovogusoxegimo.pdf
    • https://nisahanpin.com/calisma2/files/uploads/mawewujanifelu.pdf
    • http://benthanhsgfarm.net/images/uploads/files/89492573134.pdf
    • https://southwestlooms.com/admin/userfiles/files/gixop.pdf
    • https://linkevicius.com/upload/galery/file/fumeb.pdf
    • https://olgunbey.com/upload/ckfinder/files/wasoxuvarajisaxo.pdf
    • http://888spirits.com/userfiles/file/togaxezafavidet.pdf
    • http://skene.es/userfiles/file/20448543788.pdf
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/ntmugqr7ghj0s22jbgp5ep6gnf/bamutatofolikazijabeme.pdf
    • https://kirmatas.com/userfiles/file/rofixobobajixufu.pdf
    • http://tuzvedo.hu/elemek/file/53817706662.pdf
    • http://abwingssuffolk1.com/uploads/files/roluvekapogupagikurema.pdf
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145adab29aed---50044914330.pdf
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142b73c92109---4972097604.pdf
    • http://riskhedgetech.com/uploaded/file/1003989541613ffa46dd43a.pdf
    • http://vaness-sens.fr/ckfinder/userfiles/files/wewezajujimelasalarad.pdf
    • http://leasingtowers.com/ckfinder/userfiles/files/tetadabubosa.pdf
    • http://floridadressyourhome.com/uploaded_files/userfiles/files/66977716239.pdf
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/06d0992bfedb8aa598efb87c8c2db32e/30161522512.pdf
    • https://agencement-menuiserie-var.fr/stockages/files/91062096521.pdf
    • http://www.tobywells.org/media/fckdir/file/44025226282.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_off0000bc7b.bin
379644b92fe3075d0741082ea3df8ac40436e8bc5af5d5e97d443280416763c3
pdf-font-stream PDF embedded font (sfnt) at offset 0xBC7B 19700 bytes
font_01_sfnt_off0000ef8c.bin
0fe191e753b4ace32be7a470f60492546e64222e74770d89fcbe10cf52509a07
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF8C 10256 bytes
font_02_sfnt_off000106e8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x106E8 16792 bytes