Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7ce31674f9ef8f8…

MALICIOUS

PDF

169.0 KB Created: 2021-07-18 01:17:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3a50796106f78c1c6494e847a5bcf566 SHA-1: 1a56c58140fd21360fec7ebe54538f7e0e7108ab SHA-256: b7ce31674f9ef8f8e6f6fe15eb0b7e8c08cb5a2ef070a70ec940478276b4d655
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous URLs that point to compromised WordPress upload directories. These links likely serve as lures for phishing attacks or to distribute further malicious content. The presence of multiple distinct hosts and the use of disposable hosting indicate a deliberate effort to obscure the true origin of the malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9103

Heuristics 6

  • 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.
  • 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://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/160987ba62982b---86837399452.pdf
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/880112e3e753fb5ac148c23fc063a4cb/5093369652.pdf
    • http://aprendanow.com/wp-content/plugins/super-forms/uploads/php/files/07c2a027f5cad6dfd5312eb8321be8a5/devosumigiva.pdf
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160846ca7d34ae---nupan.pdf
    • http://puppies-4u.com/clients/e/e7/e7f09595da74c05d2059c741134300d2/File/nugasove.pdf
    • http://sshs61.com/clients/6/60/60e739d5a8cf4a6710e4f064fd99417d/File/naguxipinosajotiburipa.pdf
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/36n0nsrj2k7hku7lhf91f9coc2/vijakizujusezeb.pdf
    • http://smart-ventures.ch/upload/Editor_Images/files/65050557155.pdf
    • http://www.irrv.org/uploads/files/2478909438.pdf
    • http://triatlonbizuterie.cz/sites/default/files/file/wuvuvunut.pdf
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607674e588c76---dinetuliferepeluk.pdf
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/16084f0b0eb40a---94587639775.pdf
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/kue08fmsa3rjh1l0abfn2ck386/bosukanamabajivil.pdf
    • http://abimobiliare.pl/pliki/File/55786827111.pdf
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/8cae0e768d60b7ae4d4111b8907905b6/80082658082.pdf
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160909fc92fe69---gapikawividadikufifusur.pdf
    • http://geyikkimya.com/userfiles/upload/file/ritotorur.pdf
    • https://alnahamgroup.com/userfiles/file/17458363397.pdf
    • https://readandenjoy.ae/userfiles/files/xikipewema.pdf
    • http://pk.mo/userfiles/file/48614015705.pdf
    • http://automsystem.com/UploadFile/file/20210513085857759.pdf
    • http://erdivigado.hu/userkepek/file/mevowamoraxanurupepaf.pdf
    • http://xn--or3bi2da319p.com/upload/fckeditor/file/lebodepogugoku.pdf
    • http://pauseforserenity.com/clients/1/10/1002a5d8b3740fc7390aa1937d1ec3ed/File/tujasubogewo.pdf
    • https://morabia.fi/images/file/xotifonalivepojefogitogug.pdf
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/s6vj284jbcj91eq7jciqjfbuq1/lifodiritunobome.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=what+am+i+to+you+answer
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00021280.bin
2f6603e31a01699d5d6ef754e08fcf11556492e2e455a991711e6ae68c02e5f4
pdf-font-stream PDF embedded font (sfnt) at offset 0x21280 19368 bytes
font_01_sfnt_off00023381.bin
7df27ec8284e74525c0ff488080f0b44f0363ac10b8a71a18d7eb6ac06facbef
pdf-font-stream PDF embedded font (sfnt) at offset 0x23381 10620 bytes
font_02_sfnt_off00024bb5.bin
05e751ff3a228c6c5540be139d96702607dd52bea4d2a3901e7673b4bba8a0a4
pdf-font-stream PDF embedded font (sfnt) at offset 0x24BB5 20548 bytes
font_03_sfnt_off00027de7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x27DE7 16792 bytes