Malicious PDF — malware analysis report

Static analysis result for SHA-256 2db38ae3fc793a20…

MALICIOUS

PDF

84.9 KB Created: 2021-08-15 22:27:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 312d5bcd718d21d86248c97ca88c2143 SHA-1: e642c7b514beedcab754338f582fd1dd9b41f4f6 SHA-256: 2db38ae3fc793a20935ee64e27eae97da2517e00f80787e2a018dfef2100769c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs that point to various domains, many of which appear to be compromised CMS uploads or link farms on disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of creating numerous links on different hosts, suggesting an attempt to manipulate search engine results or distribute malicious content. No scripts were extracted, but the overall structure and URL distribution strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://krisoc.ru/uplcv?utm_term=how+much+is+80cc PDF link annotation
    • http://cerescommoditiesltd.com/Images_upload/files/79222935145.pdfIn PDF document text
    • https://seerupit.dk/assens/file/68864478682.pdfIn PDF document text
    • http://patriabrno.cz/userfiles/files/gaxila.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a62cafbe9ee---96966165518.pdfIn PDF document text
    • https://kawanmto.com/contents//files/5877952.pdfIn PDF document text
    • https://gruntbudowa.pl/files/file/11048235177.pdfIn PDF document text
    • http://ilturismoinitalia.it/userfiles/files/75879712796.pdfIn PDF document text
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/6b464309be749dcb1103433b3898037a/88498537790.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/ah5fpenvfjl6iss8181ahtmah8/21904015090.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a41add17726---silataxuxemas.pdfIn PDF document text
    • https://riolospettacoli.it/filesUploads/file/texebasabovanit.pdfIn PDF document text
    • http://olneyjune65.com/clients/d/dc/dcef5d22f85ec69f5810ba62c2e8cf46/File/33315892755.pdfIn PDF document text
    • https://avistravel.ro/userfiles/file/nenisefeluzek.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1607f13e5caa41---15463579136.pdfIn PDF document text
    • http://zaragozalawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sogatemofujagitixodob.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/2dd493fc1efa96d48a9e4f2191869df7/xawizepuxodano.pdfIn PDF document text
    • http://billsky.ee/files/file/vulixipemubip.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160f1cd06ab687---ruteguf.pdfIn PDF document text
    • http://jacsonsfurniture.com/userfiles/file/filagesedozif.pdfIn PDF document text
    • https://www.ojchamber.com/ckfinder/userfiles/files/kefajanetazobagejasena.pdfIn PDF document text
    • http://au-coeur-du-temps.com/userfiles/file/gipokodunalakanigoko.pdfIn PDF document text
    • https://whatshoulditcostme.com/userfiles/file/83044453194.pdfIn PDF document text
    • http://leinerpakgelatine.com/survey/userfiles/files/bisitofi.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_off0000e87f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE87F 10360 bytes
SHA-256: 6a723ea2e537c96f4d079ef64f333e11c1c727d98b8c72bc38e305ac2ee863b2
font_01_sfnt_off0000ffeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000117fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117FD 17304 bytes
SHA-256: af380fcf9c02b9546e58c185559b6eb7b210a8f3c424b6e7d126a3bd46055b9d