Malicious PDF — malware analysis report

Static analysis result for SHA-256 31a2491abdcd111c…

MALICIOUS

PDF

80.0 KB Created: 2021-08-02 14:27:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 2bdadec7c5b023dae9268298f662e118 SHA-1: 976667514c60e9979c05f26e708ae60e2cb8158f SHA-256: 31a2491abdcd111c6d73695f124934178abeb06d1792e9434ff876b07d5636f0
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL analysis point to a common tactic of using compromised infrastructure for distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://mesahighclassof64.com/clients/874441/File/61773851620.pdf In PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/c46c3c54fcc3e2657ecf108aa4e8f23c/siduno.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160da39b029ec3---49521036052.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ccee2a9769---tikarebi.pdfIn PDF document text
    • https://karinbentum.nl/uploads/file/malewugokifilumelig.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/969af2fd3e29ad3b1537c5dcc84f92f7/1213748834.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9f655067f---liwaxamujosuxofeduraso.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/3829754254.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160753d20d4589---56762698522.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/fgt5rop2bg45vr1m3roe9e9lu5/67176952532.pdfIn PDF document text
    • http://ski-experience-japan.com/images/blog//file/sefejedodivefuperej.pdfIn PDF document text
    • http://gagutp.com/sa_upload/userfiles/file/20210714094659.pdfIn PDF document text
    • http://cnokorea.com/userfiles/file/tegakimexozukiwagoguda.pdfIn PDF document text
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/fa716319f93ca62971b31e5f4c0b11e6/kexazikevawelosofega.pdfIn PDF document text
    • http://laulumaja.fi/ckfinder/userfiles/files/favivejanibuvatafodifi.pdfIn PDF document text
    • http://aldara-latinoamerica.com/userfiles/file/8101872800.pdfIn PDF document text
    • http://datavincity.com/uploads/ckfinder/files/vedezovedakenipedomudoji.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/vrrh002b05qaaoo4ieo8tjk9d1/lunitu.pdfIn PDF document text
    • https://tecnibat.net/uploads/archivos/55827169931.pdfIn PDF document text
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/osvlnhgd5dslflsohvuf2dsjl1/raxazazibole.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/81c4c9a6d0124e7594cf89c713a3b37c/41152463598.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160782935b5148---81133192399.pdfIn PDF document text
    • http://simonide.org/userfiles/file/4751317768.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=how+to+turn+on+backlit+keyboard+acer+nitro+5PDF 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_off0000d154.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD154 18012 bytes
SHA-256: f62827ef62c4ae37a23d33dc8585dbc243f99d885222a03ee4bee57ae7087e2f
font_01_sfnt_off0001009a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1009A 10852 bytes
SHA-256: a0933341b127ac43d8ef88d57830a9f56ff934fb7ecde0226ec24bd2f95385c3
font_02_sfnt_off000119d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119D9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1