Malicious PDF — malware analysis report

Static analysis result for SHA-256 90a588ce16e387b9…

MALICIOUS

PDF

81.2 KB Created: 2021-09-22 10:31:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 9c6ba174843507f73d97fc728594c138 SHA-1: 7288cbb10a735ddca3132120a45eaabc11df8b27 SHA-256: 90a588ce16e387b994ffcb83c45f5a101323f1ae256ade3fd1976be220e33a61
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed to artificially inflate search engine rankings or distribute malicious content via a network of links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://crewmak.ru/uplcv?utm_term=mobile+data+not+working+on+android PDF link annotation
    • http://speakingaboutnetworking.com/ckfinder/userfiles/files/25148370511.pdfIn PDF document text
    • http://silverk.ru/img/lib/file/melisamolubesoduxid.pdfIn PDF document text
    • http://contua.org/userfiles/file/43609059182.pdfIn PDF document text
    • http://holidayservicemarsala.it/userfiles/files/17562269782.pdfIn PDF document text
    • https://agros.net/uploads/file/bulidimiseromefevix.pdfIn PDF document text
    • https://thefertilizergranulator.com/d/files/zojajakuwoziv.pdfIn PDF document text
    • http://jikaramen.com/uploads/files/lozomagitanopubu.pdfIn PDF document text
    • https://akrmedia.no/ckfinder/userfiles/files/75818111870.pdfIn PDF document text
    • http://centrons.com/uploaded/file/4898048496130e2c2d66ca.pdfIn PDF document text
    • https://satesayap.com/contents/files/gilegipazujafufituvelo.pdfIn PDF document text
    • http://fkm-lux.by/var/upload/file/49826617426.pdfIn PDF document text
    • http://italianopizzeria-pg.com/uploads/files/82097322629.pdfIn PDF document text
    • http://sireny.net/share/files/92516549537.pdfIn PDF document text
    • http://fantalife.nl/userfiles/file/jubelepusig.pdfIn PDF document text
    • http://www.cerel.eu/images/wyswig_images/file/16823605248.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/ce6042deef308904b55a161b97779bc8/ripodugol.pdfIn PDF document text
    • http://linklandhotels.com/upfile/editor/files/nukejasinivopunonejexufe.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/5bc4f20735ec9f5ee8c326e79b57b71c/72770061847.pdfIn PDF document text
    • http://conomiya.com/images/uploadedimages/file/zisorejupisekufox.pdfIn PDF document text
    • https://network-italia.com/file/76247586725.pdfIn PDF document text
    • https://dcoderesearch.com/uploads/59286538667.pdfIn PDF document text
    • http://stalmont.eu/userfiles/file/9958319674.pdfIn PDF document text
    • http://owv-sad.de/userfiles/files/joxazojubevuvifaj.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/1r68745ghblsf184pga7b64cgg/xegurijeko.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614226baeae63---pobeliju.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000da26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA26 17284 bytes
SHA-256: a3eb6dd6310a84c992af95405177c0423dcdcdc1eb70acb92d091c2181f1091c
font_01_sfnt_off00010715.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10715 10568 bytes
SHA-256: 22274b91bb56f4ec3a1a617a5fcca8f794b00696a31c4f70e647fdfb110fbbb0
font_02_sfnt_off00011f25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F25 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1