Malicious PDF — malware analysis report

Static analysis result for SHA-256 16d75866ca384773…

MALICIOUS

PDF

73.7 KB Created: 2021-09-01 23:03:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 608aa9a74042c21de5b649babd7b6663 SHA-1: d568336fef72e665424719f2504a936269d59d5b SHA-256: 16d75866ca38477359387e3ea3959789d9ef9458294f2a251b4c2e519e56a57d
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file that contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains. The heuristic 'PDF_RANDOM_URL_LINK' and 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate a pattern of distributing links to potentially malicious content. The ClamAV detection as 'Pdf.Phishing.Trojan' further supports its malicious nature. The presence of embedded URLs suggests an attempt to redirect the user to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://clinivetmadonnadirosa.eu/userfiles/files/xememebigu.pdf In PDF document text
    • http://www.farmaciavictoriayjmleon.com/userfiles/files/laguliwe.pdfIn PDF document text
    • http://antifftech.com/uploadfile/file///2021052819580883.pdfIn PDF document text
    • https://jamurgoreng.net/contents//files/93908053865.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16077f0ebecc80---18480087693.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080cb01ac27e---powizafemejezuvo.pdfIn PDF document text
    • http://garmagostaran.com/Upload/file/xajamivolofogo.pdfIn PDF document text
    • https://stcc-sa.com/motakamel/Ups/files/90731724313.pdfIn PDF document text
    • http://ajisushionline.com/uploads/files/25329974789.pdfIn PDF document text
    • https://gberwanda.com/gbe/useruploads/blogs/files/fakimewabexinogefojimikiw.pdfIn PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/3tkesfhfins782ee97826o760q/febufo.pdfIn PDF document text
    • http://ksnjl.com/userfiles/files/wirilikodexod.pdfIn PDF document text
    • http://kanalizace-ul.cz/userfiles/file/87197213505.pdfIn PDF document text
    • https://willmarareachamber.com/ckfinder/userfiles/files/lolowowi.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609a6b33b0542---37559915859.pdfIn PDF document text
    • http://thetachikappasigmaalumni.org/clients/5/56/56ac51e2ee760b54d3ff8b7d53c877b7/File/92168860614.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607b8fa45bb4a---71188449165.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/b786fd6e25705c8bb5d3f2331798ec10/positawamesozedumopuje.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612afeddae9b2---55216498329.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8b2ce4d2b8---varesisotofereba.pdfIn PDF document text
    • http://livestreaming.group/wp-content/plugins/super-forms/uploads/php/files/8ao88rv1enfb1kfv53ksnh8kmhteiuf6/11044429776.pdfIn PDF document text
    • http://artistalexanderkanevskyroyalshakespeareglobetheatrelondon.com/clientMedia/file/85727009310.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/37248a5a482c870cb0367a79fb21d012/12310890772.pdfIn PDF document text
    • https://pediatricpotentialsnj.com/PP/PPpng/files/52257431147.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/dejb95pj92qetbujpkqkcu4pbc/norazikuxonipusodefani.pdfIn PDF document text
    • http://vtaky.sk/media/file/79774542038.pdfIn PDF document text
    • https://psychotherapie-coeppicus.ch/userfiles/files/zixomenanosuges.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=bloody+mucus+in+baby+stoolPDF link annotation
    • 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_off0000bf66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF66 10708 bytes
SHA-256: c2698e3d53f52e900803ae91ec6abde3bf34fc465888e10c52d287bba9fc0b3b
font_01_sfnt_off0000d808.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD808 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f01a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF01A 15416 bytes
SHA-256: dc0134b739bf93141a47d04d51c7d525a80c6bafba16d72eeb593998d5e366b7