Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a86df58e31ca67a…

MALICIOUS

PDF

79.1 KB Created: 2021-08-13 20:32:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 90740bd7e03b66e35ea2cdeaeee18d85 SHA-1: f3b97291256e9efa9bc6f1ac4a412cb050da6f86 SHA-256: 6a86df58e31ca67aa1c669d227104870a551ffd2bc17df22900d83ab80f442fb
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://ultraljud.nu/bild/files/wugokolozedekemenorozuwu.pdf In PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/aba988bcef0018b00640f0972bb89754/xojijufoxikasarulosugilog.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609084b793f16---33243291906.pdfIn PDF document text
    • https://andrejc.si/files/file/resabidebirazelo.pdfIn PDF document text
    • http://xn--e42bt3l.net/upfile/files/72105202605.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/ip4fni6t2k4l7pq3gudkfclubv/zizoxugopepuvizamox.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b20ca4e827a---16020159254.pdfIn PDF document text
    • https://dm288.com/slicice/file/35811797457.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610f10024fed4---parawodiwomesapazamodu.pdfIn PDF document text
    • http://automotiveenergy.cz/userfiles/file/mafafokewemowogopoz.pdfIn PDF document text
    • http://alacarte-design.de/userfiles/file/34618071306.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/a0t6kn54lq3tg01voggnfcvtfu/vivig.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607bab402f832---napab.pdfIn PDF document text
    • http://ristoranteyuri2.com/userfiles/file/90776596648.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a029c6b73e1---74997129191.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/3d9g7f1ukon3n6ghlgnq4b3vdc/33040215027.pdfIn PDF document text
    • https://useoneconvo.com/wp-content/plugins/super-forms/uploads/php/files/dc37867cce13f66c35ab7cf49ff7c5ee/mepupifid.pdfIn PDF document text
    • http://pro-group.ru/userfiles/files/66248262286.pdfIn PDF document text
    • https://www.stock2morrow.com/ckfinder/userfiles/files/49813486403.pdfIn PDF document text
    • http://industrialsupplies.pk/userfiles/files/motopafotabozikodul.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/33d2272d51dee78b290bdd28c7e5b37a/29193675455.pdfIn PDF document text
    • http://vietnam-intraco.com/webroot/img/files/mugexitovib.pdfIn PDF document text
    • https://cryptobasics.biz/uploads/files/wikaturixajemuwaturip.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=bedwars+map+download+hypixelPDF 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_off0000d133.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD133 10916 bytes
SHA-256: a9a3cab31dd6dd7194531fcfa41fdbdd06659ce9a082188f01abfc95876a12d0
font_01_sfnt_off0000ea51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA51 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010263.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10263 16796 bytes
SHA-256: 6bea12cc8cff8e4e4907a3c617e9b096374b3d9e2b4558fe4ed0a79790415361