Malicious PDF — malware analysis report

Static analysis result for SHA-256 b83804d6875db72e…

MALICIOUS

PDF

76.8 KB Created: 2021-09-03 20:20:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ccb5f9b8f7fecbfd6afe69259c866e0b SHA-1: f926a1f11c8369ee71b1b5f487c50a77346bc846 SHA-256: b83804d6875db72e0608b52a493e094e883c35707a16ac5c98b5bf01165fddae
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to external resources, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the PDF structure itself is used to host and distribute links to further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ddbc27eec7d---xebadu.pdf In PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fc2ef8a326---24898794270.pdfIn PDF document text
    • http://villaelen.it/userfiles/files/kixosubi.pdfIn PDF document text
    • http://www.css-jp.com/upfile/files/2021/06/26/14178406552.pdfIn PDF document text
    • http://covinahigh1980.com/clients/1/14/147ee80f0cf2e08ca1b5067d21485a43/File/51736048956.pdfIn PDF document text
    • https://balajihighfields.in/userfiles/file/97452111674.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160702388edd58---70758310705.pdfIn PDF document text
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/xulor.pdfIn PDF document text
    • http://hnc2.com/userfiles/file/73348806922.pdfIn PDF document text
    • http://abwninemile.com/uploads/files/mogux.pdfIn PDF document text
    • http://futsalcb.cz/picture/vtextu/file/menapazowujuzaw.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160988b6457e2b---zebujabovavifobowis.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/b6a53cf6d187c689fdc324490b532dc7/maxomavukazijutoze.pdfIn PDF document text
    • http://stardentalcare.org/userfiles/file/99007927686.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ee7896d239---67542523050.pdfIn PDF document text
    • http://smit-electronic.hr/upload/datoteke/vidikodeniwiledigej.pdfIn PDF document text
    • https://space1500.com/wp-content/plugins/super-forms/uploads/php/files/bd9b8bdfcff7e16e5beeb188896d221d/lagezene.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1609eac267676a---gapifoborabaxugobirexemi.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/c97fea963e14ce27c916115af98edc4e/9751241998.pdfIn PDF document text
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/71585731574.pdfIn PDF document text
    • http://jhroseclassof77.com/clients/45984/File/dawuladikefinalefabaz.pdfIn PDF document text
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/59f104261b4b17de853aa377d9111895/52900652111.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160788ab34a5a4---zimanivesiroxo.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/8j5bfuiljibcsum2amlck40ee0/sapefumodagokin.pdfIn PDF document text
    • https://selispin.com/calisma2/files/uploads/tovukodip.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/62488299458.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=analogies+worksheet+answer+keyPDF 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_off0000cab1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAB1 10660 bytes
SHA-256: 4f59a31543c438ae170468ccf35f596b70987746bf43961c7546bdc38854a35c
font_01_sfnt_off0000e332.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE332 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fb44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB44 16620 bytes
SHA-256: 21266890ce96531ba51ff5a39ad5afa4482b5f324e0bd1db6ce7ffe15e426fd3