Malicious PDF — malware analysis report

Static analysis result for SHA-256 535a3fc7b137e834…

MALICIOUS

PDF

73.7 KB Created: 2021-09-25 05:02:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 43d2376f959076d32af2f63fa97cc9f7 SHA-1: 0fa4f6c2a78b10ce7c9272e6d4b3858dba482b38 SHA-256: 535a3fc7b137e8347d8d7ba0b28bd21dcc82602fe7460c815fd038b2ebc8ca03
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest 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 host malicious content or redirect to phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 http://yourmoneyyourbank.com/uploads/File/sadidabimu.pdf
    • https://allegypttours.net/userfiles/files/56980165320.pdf
    • https://matkinhantai.com/luutru/files/bufugubom.pdf
    • http://herborgthailand.com/file_media/file_image/file/22686895626.pdf
    • http://wisdomtours.net/upload/file/tupitimokexewaripibixix.pdf
    • https://mimpishio1bet.net/contents/files/82901231651.pdf
    • http://thietbikhachsanvinhhung1.com/upload/files/forapowasodisig.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1614b1d37cd4b0---11334882591.pdf
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/161387103ec8c3---vibukowudidagusekutuvoz.pdf
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/1614c44fc95f01---19608197308.pdf
    • https://ceramicasvillaflor.cl/UserFiles/File/95633117999.pdf
    • https://red-adlay.com/upload/files/30917896401.pdf
    • http://yanarfabrics.com/firma/files/lidabigorilejiduri.pdf
    • https://heuresromantiques.com/upload/files/32250795521.pdf
    • https://kaparatt.com/images/File/siwewatag.pdf
    • http://gzperson.com/uploadfile/files/42269485965.pdf
    • http://travellightnepal.com/userfiles/file/66142474022.pdf
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/161323c61a4ad1---jetegipapem.pdf
    • http://gewidor-gmbh.de/uploads/files/73499444003.pdf
    • http://sportsbettingconsultants.net/cote_dor_import/admin/ckfinder/userfiles/files/3680294590.pdf
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614113ab68d51---92092792114.pdf
    • http://partiaweb.ir/upload/files/pabejimotosofenusad.pdf
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161341e7dafec7---23993973440.pdf
    • http://laihoawedding.com/app/webroot/upload/files/40420658778.pdf
    • https://franchisefarm.franchiseharbor.com/files/files/kibagopuvezudutagopozav.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=zawgyi+to+unicode+app
    • 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_off0000b707.bin
38cac4919d16c6c62ea467b826765b045dfbce32e04065cddcd49123a57e6b9c
pdf-font-stream PDF embedded font (sfnt) at offset 0xB707 10640 bytes
font_01_sfnt_off0000cf65.bin
e46f158f7e5b89639804917049c521d08edc991660d8c04ae7d966f8874dc73e
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF65 19076 bytes
font_02_sfnt_off000100f3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x100F3 16792 bytes