Malicious PDF — malware analysis report

Static analysis result for SHA-256 84d84b9c2efe885d…

MALICIOUS

PDF

72.2 KB Created: 2021-06-12 10:39:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 4878afb4bce9a4275f3a61f1ff623bf7 SHA-1: 5e869979f4a63a0bd319ebca70f403b9223486ed SHA-256: 84d84b9c2efe885d036a0e99793091a8a4204b3c654780b5172d73b65476c84a
226 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a fake browser/software-install lure. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://infrive.ru/pbw?utm_term=eldest+pdf+download PDF link annotation
    • https://mavusuwavonim.weebly.com/uploads/1/3/4/4/134493404/fijuwefof.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473056/normal_602d9f01e34e3.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4459482/normal_60b4e66782895.pdfIn PDF document text
    • https://xuniwinasifobip.weebly.com/uploads/1/3/5/3/135302293/b236bfb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459784/normal_5fd12e504b9e3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475734/normal_60c1aaf6a0856.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4388177/normal_5ff681d3ad534.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454422/normal_601689d84343f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4376857/normal_600134522fac7.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4391305/normal_600353ac5e4de.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410206/normal_604e152ddcc96.pdfIn PDF document text
    • https://rijivujebevobog.weebly.com/uploads/1/3/4/4/134488471/61a92bf4f0fb87.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446500/normal_60360bc166491.pdfIn PDF document text
    • https://kopikemuv.weebly.com/uploads/1/3/0/7/130740389/4accbdc4e7.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/52e22d48-bbc1-4602-a8fa-b835c50e677f/sp_racing_f3_gps.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3586098f-9ac8-49a9-be90-aea05b2edc75/pokerizutovapakobewalurat.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/933f68f6-5509-43c2-9c7e-51e85819dab0/easy_tablet_weaving_patterns.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/714c4ed6-7772-4a21-a977-55947c257b1f/guess_the_brand_answers_for_iphone.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1c6c1fcf-6cee-4e10-9d4f-07748078c32e/1499722252.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/023fbf6a-6f26-43df-a695-0162c39e197f/gta_san_andreas_btn_grevleri_bitirme_hilesi_indir.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cb118118-0cb0-4944-bef1-ff6a30a766da/multivariate_analysis_in_jmp.pdfIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dd74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD74 4988 bytes
SHA-256: 0f6deeac1e62ecdd246437cc1bcc4967154f5db63ca174b67b2b16fdfaf6cfc7
font_01_sfnt_off0000ee96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE96 10508 bytes
SHA-256: c2a68a9282434264bf92bfcb0df69a370f3fbbfdddb1d7b85f48994a9cf13a19