Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8ad365a84b6e70c…

MALICIOUS

PDF

126.1 KB Created: 2021-06-25 14:56:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2026-06-05
MD5: b40ac6104b8a5796aa37fc6ef07cb838 SHA-1: 30483d9972d6631cd9e9f0ac2194505d40a541d9 SHA-256: a8ad365a84b6e70c3a2e12199c218a1cee0bde08a60e33f8c4fe7b746f0e0866
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress upload directories, indicating a link farm designed to host malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution via these compromised sites. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient for this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c310d35cf0---13234357244.pdf In PDF document text
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/alam1aenropkdi2fnmc83fvq0h/84257596880.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/n08ihatlp3qmbkabktqpjfa041/dujijozesobukugew.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/008cd89b50ba687252bacca654901bfe/rojukirurumexoruwo.pdfIn PDF document text
    • http://talleresjpg.es/img/file/39277396999.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/487c45dddb8efa211cfaaa7cd1e6f59b/muguxoxid.pdfIn PDF document text
    • http://riph.pl/userfiles/file/lazefunujuwaz.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/ec1045d7elp4muiet0dsvavep4/duwububerovekiwiliruv.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/43b209c08ac1bb88f228c5268583c462/1551195553.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608387ebc0bd1---fegoranosekawoz.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c5ff0afcb2---4591277912.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/160779e560ca6b---30475668028.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c0f9142b52f---23385253472.pdfIn PDF document text
    • https://alarouba.com/ckfinder/userfiles/files/76483423128.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=the+bacchae+and+other+plays+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_off00018cff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18CFF 17496 bytes
SHA-256: 3359423fc8439288f1e2599373c7b13fa2550422089d90635d8b576baa7b0c3f
font_01_sfnt_off0001bafa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BAFA 10844 bytes
SHA-256: a98a5c5a2b4db317c21efdb265765377dc9575bd55cce0abb831c54660f460d1
font_02_sfnt_off0001d3ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D3CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1