Malicious PDF — malware analysis report

Static analysis result for SHA-256 4757dcf4d113b683…

MALICIOUS

PDF

77.9 KB Created: 2021-09-07 02:54:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: b05c106625200f0ae757274a3e6fd64c SHA-1: 935a2e8093a22bcc846a710ef27051de28483968 SHA-256: 4757dcf4d113b683d26ec8bf337d5f2112cfff0d37a662fe6a8651ed8fcaf0c1
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to lure users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://ketchas.ru/uplcv?utm_term=alimentacion+y+nutricion+definicion+pdf PDF link annotation
    • http://police8coop.com/UserFiles/file/pizam.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5fd9827a67---23918750309.pdfIn PDF document text
    • http://clair-environnement.eu/catalogue_dynamique/file/nisiru.pdfIn PDF document text
    • http://bouwbedrijfbouwheer.nl/userfiles/file/67641077906.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/86743865668.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/cqp2465g6jol6s3onh8ao165lk/vafekosusadipegitisujaso.pdfIn PDF document text
    • http://datong-travel.tw/upload/ckeditor/files/20210810120712.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/61291376210.pdfIn PDF document text
    • http://accessprecision.com/userfiles/file/24671618712.pdfIn PDF document text
    • https://classykitchen.pl/web/uploads/files/25558845078.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/11153b54b38de78d8bbbd4c1cc4a208b/17459671972.pdfIn PDF document text
    • http://alliance-ic.ru/uploads/file/66905843870.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/84c0b297cb60c40027a99303b80d3ac7/radukotofoter.pdfIn PDF document text
    • https://apotekatia.ba/fajlovi/kinugefukiwirafi.pdfIn PDF document text
    • https://anandamsanyal.com/userfiles/file/terizadezolebenarepomiwi.pdfIn PDF document text
    • http://handsonmontessoripk.com/userfiles/files/39729941464.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c6dc92706e8---jadoxeruvadodanamil.pdfIn PDF document text
    • http://robertoantoniz.com/resources/original/file/79920304885.pdfIn PDF document text
    • https://bestcoloringpages.com/userfiles/file/konilevukibuv.pdfIn PDF document text
    • http://fsf-vastroad.com/userfiles/file/6343388656.pdfIn PDF document text
    • https://sikdercollegeofpharmacy.com/scp/ckfinder/uploads/userfiles/files/27504952940.pdfIn PDF document text
    • 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_off0000cd3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD3D 10808 bytes
SHA-256: 5af9c2d2561517048ad58a080f4bb9383eafb60c0a94f265881fd4f5347b34b4
font_01_sfnt_off0000e62a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE62A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fe3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE3C 17480 bytes
SHA-256: af4deb4cd4e283e20f34ceef1b45929b6f86b91740029e0f9f609adf24be1dfe