Malicious PDF — malware analysis report

Static analysis result for SHA-256 631c351ec2c5ba1a…

MALICIOUS

PDF

81.9 KB Created: 2021-09-08 23:29:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 8020a44f2884199bed4ccf3d399c4fe3 SHA-1: 9684a13539c9bdfea5bc58b7304da114167df4eb SHA-256: 631c351ec2c5ba1aaf9d772415a5efe476cdca4fb37da244f92246385ec083c7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs pointing to other PDF files hosted on potentially compromised or disposable domains. The presence of multiple links to unknown PDFs suggests an attempt to lure users into downloading further malicious content or visiting phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://path.mn/userfiles/files/wotupeguxitupuz.pdf In PDF document text
    • https://alusol-kw.com/ckfinder/userfiles/files/xalomilozojivopulom.pdfIn PDF document text
    • http://snft.ro/media/file/gozokomibomiripof.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132dbe8542bb---97404352991.pdfIn PDF document text
    • http://execdentalclinic.com/uploads/ckfinder/userfiles/files/debez.pdfIn PDF document text
    • http://mbjarrahi.com/UploadedFiles/New/file/80271835972.pdfIn PDF document text
    • http://triple-a.co.th/ckfinder/userfiles/files/69494847312.pdfIn PDF document text
    • http://web-news.eu/www/pkpar/userfiles/file/fedunesoguwemogolerimad.pdfIn PDF document text
    • http://www.vegagastro.pl/upload/file/xemizolalutaz.pdfIn PDF document text
    • http://bangdinhphucat.com/quangbasanpham/app/webroot/upload/image/files/zugaxuraduwufaxebezusixoj.pdfIn PDF document text
    • https://valleyrentals.com/userfiles/file/24570306482.pdfIn PDF document text
    • https://dodomacnosti.net/data/file/90869874914.pdfIn PDF document text
    • http://otpetye.com/images/shared/file/weriwikazuvitagemasavebop.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/b9b832814e37398f3660ce3e6ad82f0e/60940874600.pdfIn PDF document text
    • http://jplus-ag.com/upload/files/BodyFile__613096B35B63A.pdfIn PDF document text
    • https://pachetedeturism.ro/images/files/xakijozosaku.pdfIn PDF document text
    • http://eurekaelearning.com/upload/news/file/71675192932.pdfIn PDF document text
    • https://bdata.vn/upload/files/tivegijubuzavivat.pdfIn PDF document text
    • https://bevillelecomte.ovh/ckfinder/userfiles/files/xagusiminasakuvo.pdfIn PDF document text
    • http://ndc-group.ru/uploads/files/sonosaminitani.pdfIn PDF document text
    • http://harringtonassociateslaw.com/Test/JabzMedicalBillingService/userfiles/file/xudotiwewa.pdfIn PDF document text
    • http://gmicropilotes.com/uploads/files/gisajenobesaxadadatiweleb.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd373d3d89---56758419870.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=what+is+a+conjunction+in+a+sentencePDF link annotation
    • 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_off0000da4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA4C 18432 bytes
SHA-256: e9f79dbde00ed25755727234dde46c6c8a88df46cfd6136532e8a37453fcf13a
font_01_sfnt_off000109fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109FA 10404 bytes
SHA-256: 17555f20811621f9066cbc7de0b2df8486b935714538120abbc7ef7e89930c1f
font_02_sfnt_off00012187.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12187 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1