Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec1ea8f5e5b89ff4…

MALICIOUS

PDF

80.7 KB Created: 2021-09-16 14:11:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 66e7b2c5605f89249cd3268428650372 SHA-1: c3df4e554c30488de8d1bd35e603ff12dff515d7 SHA-256: ec1ea8f5e5b89ff4fc174e28fe47a0c5c7b81329d0ef5b714b2959b3ab339f7f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple disposable domains and compromised WordPress uploads, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were directly extracted, the PDF structure and embedded URLs are indicative of malicious activity, likely related to spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://zenit-npk.ru/files/file/palug.pdf In PDF document text
    • http://needychild.org/ckfinder/userfiles/files/dofopamevipuvasotexew.pdfIn PDF document text
    • http://muszempilla.com/files/file/57138893548.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/8fe55d5e87cca14b3710cc97f186b19d/52780475738.pdfIn PDF document text
    • https://buzascsaba.hu/userFiles/file/24619481109.pdfIn PDF document text
    • http://club-integra.ru/userfiles/file/80527960559.pdfIn PDF document text
    • http://land89.com/ckupload/files/livep.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/09/11/file/xizadekogugopazazu.pdfIn PDF document text
    • http://orderkai.com/uploads/files/5422046884.pdfIn PDF document text
    • https://mai-avto.ru/upload_files/file/wosuvobobogi.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cf9eb6dc36---lebagadogo.pdfIn PDF document text
    • http://metaglas.kr/userData/board/file/84927625594.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/16131bd2f50616---75355876191.pdfIn PDF document text
    • http://haai.org/upload/file/beraride.pdfIn PDF document text
    • https://webvitamin.vn/app/webroot/uploads/files/tubetugixosanijaneriwe.pdfIn PDF document text
    • http://robfredo.com/userfiles/file/66058197989.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613a0b3123de8---70638735997.pdfIn PDF document text
    • http://palyavalaszto.hu/teszt/upload/file/95412276495.pdfIn PDF document text
    • http://dui-antidote.net/images/userfiles/file/8984663277.pdfIn PDF document text
    • http://gyndoktors.de/ckfinder/userfiles/files/jobimavuxilizuzezimuv.pdfIn PDF document text
    • https://gionggiacam.gagiongvitgiong.com/ckfinder/userfiles/files/sodokukixiv.pdfIn PDF document text
    • https://polenhosting.com/calisma2/files/uploads/93937850054.pdfIn PDF document text
    • http://rfaaa.com/UploadFile/file/20210909011106270.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=intune+line+of+business+app+androidPDF 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_off0000d2c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eae0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE0 10680 bytes
SHA-256: 9f8603daffd626ef405078e2e58208e7a52ea8bd3947ef04915e19722d7be819
font_02_sfnt_off0001033a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1033A 19284 bytes
SHA-256: 2c8caac1667e202a23fd62f38a31bcb9483b5514e0da212939b0af8786a8f79a