Malicious PDF — malware analysis report

Static analysis result for SHA-256 978a7b0d8fe25f36…

MALICIOUS

PDF

79.1 KB Created: 2021-09-24 11:58:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 879313771137c78416777b93abde01c8 SHA-1: fc9de8f65ac36abe6480cbadfb823d4bbba645bf SHA-256: 978a7b0d8fe25f361eb240b46245ffbeb2c4f29f1eaac7ad2168225a1e8513ea
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution through these links. No scripts were extracted, but the heuristic firings and URL analysis point to a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://krisoc.ru/uplcv?utm_term=john+wick+movie+tamil PDF link annotation
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/f336948ec8b9379f7b8b9ff1c5145de8/wabidiriboresiparofu.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/87248689357.pdfIn PDF document text
    • https://contabil-fiscal.ro/mm/file/65895551471.pdfIn PDF document text
    • https://bem-sa.com/img/file/reguwimibapojidavutisokew.pdfIn PDF document text
    • https://oazapiekna.com/zdjecia/fck/file/vozonesurupu.pdfIn PDF document text
    • http://efuegypt.org/userfiles/file/22575701328.pdfIn PDF document text
    • http://abcbyspu.com/ckfinder/images_store/files/59829648364.pdfIn PDF document text
    • https://mitrasuksesku.com/userfiles/file/jajawi.pdfIn PDF document text
    • https://binarbaidtrading.com/public_html/userfiles/file/pebaninamanexege.pdfIn PDF document text
    • https://prcomponents.com/ckfinder/userfiles/files/wagaloji.pdfIn PDF document text
    • http://shengyaweb.com/uploadfile/file/2021090222162998.pdfIn PDF document text
    • https://mamotato.ro/userfiles/file/92752326051.pdfIn PDF document text
    • http://tuttotop.com/userfiles/files/39357948136.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/n8s924qri6mqbsuvfd16sm2d45/68057210697.pdfIn PDF document text
    • https://posh.hr/files/genalo.pdfIn PDF document text
    • http://learningkey.org/userfiles/70760004438.pdfIn PDF document text
    • http://alajwakh.com/uploaded_files/userfiles/files/94664508765.pdfIn PDF document text
    • http://fw-simple.com/uploads/files/dadumupumuv.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/543d87e41c969313fc94b815859f71c5/30534054456.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135caffe438b---gadof.pdfIn PDF document text
    • http://vinhthuan.com/upload/files/nalujaxudokeledoz.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_off0000c4e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4E1 23816 bytes
SHA-256: 1b0c5291ea0efa622f65c140b694113bcb758a83173e2706e9da157f80f7a5ef
font_01_sfnt_off0000ffce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFCE 10464 bytes
SHA-256: bae459784cf74a5bbc529d790cefd5c903be1d8bc2b57279d458be0f342139d3
font_02_sfnt_off00011777.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11777 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1