Malicious PDF — malware analysis report

Static analysis result for SHA-256 2916cd13b81d11b9…

MALICIOUS

PDF

76.7 KB Created: 2021-07-13 03:54:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: d74c1d7243d6b1a6dca2e08b86872622 SHA-1: a93d1cfcf08e207143db4e70171843b7a3898e19 SHA-256: 2916cd13b81d11b932bad2ffbb36c0340e80ecd0a426fb99609648316d71aa44
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or SEO manipulation scheme. The document body was unreadable, but the presence of numerous external links strongly supports the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 http://glassco.ca/clients/9/99/99aa1728c1dafa3cf8773a75727b87c9/File/10064403219.pdf In PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/mdv36554e14uqsrdojligifj6o/83351480974.pdfIn PDF document text
    • http://ippinnudon.com/uploads/files/26192760691.pdfIn PDF document text
    • http://com123.vn/uploads/file/govukaxuxolajidexa.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/33efnkm24o1nnct70g97repgi0/badofupukosavalanaduwe.pdfIn PDF document text
    • http://soflocops.com/clients/67403/File/solosafotupe.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609dab66a33f4---sasoradovutejamagiwusu.pdfIn PDF document text
    • https://lonnebacka.se/anvandarbilder/126/files/33912871697.pdfIn PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/160709920b954d---5507002525.pdfIn PDF document text
    • http://csc-0411.com/userfiles/file/20210625051702_fn4h55.pdfIn PDF document text
    • https://hazeloyun.com/calisma2/files/uploads/motizozaromobebewole.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc12490ac1---sujakutisirogab.pdfIn PDF document text
    • http://vector-luczak.pl/new/fck_user_files/file/gukukisonilafemiw.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160940e5c12b9c---53106326946.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/sirinifinuzakozob.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/61607857449.pdfIn PDF document text
    • http://billsky.ee/files/file/dimokarinemeguluxuro.pdfIn PDF document text
    • http://texmet.pl/userimages/file/libulenegerureluvojaga.pdfIn PDF document text
    • http://etabetasurvey.com/userfiles/files/21279264389.pdfIn PDF document text
    • http://www.herbertvanderbrugghen.nl/draft/xonuvodud.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079fb75b05e1---tunegulojujozab.pdfIn PDF document text
    • https://aulacvn.com/upload/fck/file/61906937511.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/zujitezirin.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/85787230451.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/jlki6io1ajkro25bgjhedop8h7/berimibunesebaganav.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/72629846275.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=electrical+safety+quiz+questions+and+answers+pdfPDF 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_off0000c8bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8BD 16332 bytes
SHA-256: 83bdb64ba283028e7cc08fad68c60e079f23f63725db129862f31e24a7e3662d
font_01_sfnt_off0000f2e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2E7 11100 bytes
SHA-256: 0c8450335864904238de77a99a3b7e7569bab689dc1f333c4a4784d2c2e0ce1d
font_02_sfnt_off00010cd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CD2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1