Malicious PDF — malware analysis report

Static analysis result for SHA-256 bfaf57cacab2d01d…

MALICIOUS

PDF

100.1 KB Created: 2021-06-25 15:25:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: f48f01b72bc14843d776e89508242d59 SHA-1: 3b7c88629e85d25a77e1e168113e794ea24617f0 SHA-256: bfaf57cacab2d01d50e77f56e6c48f151e645359176d932b18f46c02d42afc03
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and disposable hosting. The ML classifier strongly indicated maliciousness. While no scripts were extracted, the structure suggests a link farm designed to redirect users, potentially for SEO poisoning or to serve malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

Heuristics 5

  • 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://ac-kenigsberg.ru/files/file/xepinipuguworazo.pdf In PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/r7sqcfrgice49opka8p79chh30/18819497343.pdfIn PDF document text
    • https://irrisyst.eu/files/file/guvop.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c7b3eca40e6---90518677400.pdfIn PDF document text
    • http://kochamsushi.pl/UserFiles/file/tupatogomal.pdfIn PDF document text
    • http://www.publicitymailing.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160719e0906dff---88159181351.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/3162a70b15e712e336fdff069395bc31/6952858986.pdfIn PDF document text
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f60e6ed2fb---76102675064.pdfIn PDF document text
    • http://fecoil.com/userfiles/file/873858921.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/1st75dtq8ut77fj3p5ob7jp7rn/62108952093.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/dd029ec9ab493de6d4c672cd9101b503/77010669691.pdfIn PDF document text
    • http://rydelko.pl/userfiles/file/58597902695.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/162cda8ea9f4c45efe22720c6b127c3b/15797224228.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d51444ef5f4---61956460537.pdfIn PDF document text
    • https://radmangroup-ye.com/rgfiles/file/21669483161.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=most+profitable+professions+wow+shadowlandsPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010f3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F3F 17120 bytes
SHA-256: 0a4c8b4e1af9017537e1c99632dce3f9315ce13467377b43db22a0df157c3f0c
font_01_sfnt_off00013bfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BFC 10816 bytes
SHA-256: 98e2645db7a54adff02381d1f957ad6350b6621112d2c30b0ca4de1e40b6c779
font_02_sfnt_off000154b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x154B0 16312 bytes
SHA-256: 7d15b2d6d265aaca51dda18faee70a1b8fa9d95ed54cb111fb0895789092f9ae
font_03_sfnt_off00016abb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16ABB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1