Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0136099f6405b19…

MALICIOUS

PDF

90.5 KB Created: 2021-07-25 01:02:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 5626c6889c6286a19da8426b4aedce0a SHA-1: d5d1b66933bf35907150d04e2b8ab5da7c13970b SHA-256: a0136099f6405b190a5fadf999efdd0d686a93d8f1090e70922c6fa277970e6e
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 CMS uploads, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were extracted, the structure and URL patterns are consistent with malware distribution or SEO spam.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://rhodeislandalpha.com/clients/56223/File/duzelukujexime.pdf In PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/7efbebe2e513dfa4b70948440717c46c/zolupudoxupe.pdfIn PDF document text
    • https://nevisnews.com/userfiles/namusixejokuro.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f805defea9---31169288199.pdfIn PDF document text
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/42143128593.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1607e4b7e0bf50---95728016399.pdfIn PDF document text
    • https://hotnews.md/upload/userfiles/files/37657420988.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb8832d1663---xerubafedakusasojuwud.pdfIn PDF document text
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/43c60595ae755418e2174713c5cd22b4/towakowuweju.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/5c49e15fbbbcc72f263a6ef15d5e5578/64432503258.pdfIn PDF document text
    • http://ohana1bbq.com/uploads/files/13820260445.pdfIn PDF document text
    • https://pinpointfeedtech.com/ckfinder/userfiles/files/letazo.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcea3f795f5---xijeluxuvisowofo.pdfIn PDF document text
    • http://paulsaperstein.com/userfiles/files/57687753256.pdfIn PDF document text
    • http://signexpowholesale.com/project-new/christianbook/upload_images/file/janomutelubow.pdfIn PDF document text
    • http://xn--franzsischebulldoggen-lec.eu/userfiles/file/79759486866.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5adb17bb7---47100252822.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/grn2c1a81tkpkdq337h6dochfp/93968289347.pdfIn PDF document text
    • http://astro2sphere.com/admin/images/file/44011559294.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=present+simple+affirmative+negative+questions+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_off0000fc71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC71 11156 bytes
SHA-256: b69b31d372eaef69e8ffe34063238a231a9d742a7709c933975fd7f6aa85dc5b
font_01_sfnt_off00011601.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11601 17396 bytes
SHA-256: e4090afd8efd4ebe9d5a201649b94d129aad5b123480ab7a2c5975c2306e8bb3
font_02_sfnt_off000143cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x143CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1