Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a86543311cfb030…

MALICIOUS

PDF

79.4 KB Created: 2021-09-16 04:06:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 317f1b5e617bbb262e7f0625b7d361be SHA-1: 8e144098c3f6123a805070f287fbb7f4f0827651 SHA-256: 2a86543311cfb03072be758be2d2d2c59df4530bdbe0022b0537c57a64ecd359
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing users to multiple external URLs, with several hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The presence of numerous links on potentially compromised infrastructure suggests an attempt to obscure the ultimate malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614006c1ea579---gagitewuritunekutinomu.pdf
    • http://tongrentangthai.com/UserFiles/file/4637479545.pdf
    • http://velkoobchod-man.eu/ckfinder/userfiles/files/14073750808.pdf
    • http://sushikyototogo.com/uploads/files/47520538992.pdf
    • http://decaiyun.com/upload/file/210905094706314281bdkxrbbnt8uz.pdf
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/8d36c5b6a93166d378732ac1b71f9ca6/kodupulufamilonomonaruv.pdf
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/f8b9e80c68b72ead80b6da446a856b8f/tunaxoxejibedadunasekez.pdf
    • https://angelsforwarriors.org/userfiles/files/17532762546.pdf
    • http://studiopignotti.it/userfiles/files/bolasibukunoniputijuxig.pdf
    • http://pantryscan.com/123cars/imagefck/file/xuzapa.pdf
    • https://flims.atelierleuthold.ch/userfiles/files/zurivajategewex.pdf
    • https://maftplayer.net/calisma2/files/uploads/dosewetivafinonasokuw.pdf
    • https://baptistfriends.org/media/zodagamujudamopiduk.pdf
    • http://abwingssuffolk2.com/uploads/files/31723800064.pdf
    • http://www.espaciocultivarte.com/ckfinder/userfiles/files/lepipiredujapusavabimib.pdf
    • http://novafish.it/userfiles/files/wapexiwuzik.pdf
    • https://intrastorg.com/userfiles/file/lukobiwaxebuxu.pdf
    • https://mn-lawfirm.com/box/userfiles/file/sakuzukaxozum.pdf
    • http://komputerzagrosze.pl/userfiles/file/mumusodulalixuzite.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=final+fantasy+7+remake+apk+obb
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/6a4943a88d7863313c9748d72ea79c86/tiwetukupoxe.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_off0000cf8e.bin
349bae9ea3d6b3af12fdb3f8832bffe0edfd1008f51aae087edf5e8eb61e2282
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF8E 10892 bytes
font_01_sfnt_off0000e895.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE895 16792 bytes
font_02_sfnt_off000100a7.bin
0e447059813f256cece4a26b31d0553d4656903f7bb1aea795c4001d6f4bc18f
pdf-font-stream PDF embedded font (sfnt) at offset 0x100A7 18328 bytes