Malicious PDF — malware analysis report

Static analysis result for SHA-256 2441df4bbe772585…

MALICIOUS

PDF

83.0 KB Created: 2021-09-07 09:47:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7b2834079295647d8d8b0631b784bbdd SHA-1: 2d6b8bb760f23c15bf265ec062f76fa96766e5dc SHA-256: 2441df4bbe772585e4091adb7ab7dc1faef6208e5f0d105e4e21aad80f4c4790
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, suggesting a link farm designed to lure users to external sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://smidgel.ru/uplcv?utm_term=remove+blank+page+pdf+online
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/f6892acfc39074bb14800f56ee31693e/26494802825.pdf
    • https://actorconseil.com/files/file/rowipulopavitaxefalomalab.pdf
    • http://chretkinia.pl/userfiles/file/temusuko.pdf
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/2j9u8247o7507pqej82aud3s72/wazunarosigug.pdf
    • http://cy2hand.com/userfiles/77512451432.pdf
    • http://apnorajasthan.net/userfiles/file/salogiwagexaxesi.pdf
    • https://simondaulte.com/ckfinder/userfiles/files/bubakogadefowepuzit.pdf
    • http://bio86.fr/fichiers/natitisukuw.pdf
    • http://getem.pl/files/file/ribemowogiri.pdf
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/743bf8cd0dfad7b2d5870c717703874b/83245840662.pdf
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c5fd2928228---rufekemuzerokirazefolusor.pdf
    • https://vicotelecom.vn/static/source/images/file/72815712364.pdf
    • http://liweisteel.co.th/ckfinder/userfiles/files/18697287126.pdf
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160978c068636c---88684420739.pdf
    • http://thaihotelsale.com/FileData/ckfinder/files/20210708_F29CE527E53791DC.pdf
    • http://gamjagolla.com/uploads/files/48489979404.pdf
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/885ivgrqth0bc5g6amc1bu8kht/niwazovafokitopaki.pdf
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/160c04889516f1---74717696630.pdf
    • http://ji-tien.com/userfiles/file/gigeroruradirum.pdf
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/4jklaqclm0fi19dkv94t1bo845/lemufuwasatiboxivadej.pdf
    • http://www.ortodonciaelisafarache.com/ckfinder/userfiles/files/sinomafari.pdf
    • https://didacostruzioni.it/userfiles/file/10628661965.pdf
    • http://orem.mn/uploads/files/kamugerojagofexadibate.pdf
    • http://yournamebadges.com/withyourdog/cms_uploads/file/62198587493.pdf
    • https://thehouseconcert.com/ckfinder/userfiles/files/80639283329.pdf
    • http://eichler-kammerer.de/gujoxidurijagenitut.pdf
    • https://suprastoc.ro/userfiles/file/javuwafofupexofuladu.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_off0000e037.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE037 16792 bytes
font_01_sfnt_off0000f849.bin
9ae3fa370315cd9e45a68ac39dfd61d6d24ca338a23f8a48ef6af48a5c001f4c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF849 17764 bytes
font_02_sfnt_off00012579.bin
f58d5b1d91ca457f33b76cc27bd4e562d786dffdc11f8d9e3518808207dce8fb
pdf-font-stream PDF embedded font (sfnt) at offset 0x12579 10816 bytes