Malicious PDF — malware analysis report

Static analysis result for SHA-256 f16e97fb54f8237a…

MALICIOUS

PDF

73.6 KB Created: 2021-06-02 21:53:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 4ae9b278c289ca959be80b9586ded93d SHA-1: e44be21c790e6a9b6e4ad2c96a8d63647e51a7c1 SHA-256: f16e97fb54f8237ad3234e35d47ae4e4edc44a5e720bd996719cbe39e8f52277
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan threat. The heuristic firings reveal a PDF containing a large number of external links, suggesting it's part of a link farm. The primary URL points to a page with search terms, further supporting the SEO manipulation or content hosting hypothesis. No scripts were extracted, but the PDF structure itself is used to facilitate the malicious linking.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://nomylo.ru/pbw?utm_term=doodle+god+combinations+a+zagadki
    • https://cdn-cms.f-static.net/uploads/4374002/normal_606b4f66a14be.pdf
    • https://static.s123-cdn-static.com/uploads/4380882/normal_6002980a8ea34.pdf
    • https://cdn-cms.f-static.net/uploads/4477183/normal_60383e8eaef17.pdf
    • https://cdn-cms.f-static.net/uploads/4479446/normal_6046f9ea2bf35.pdf
    • https://bowefolezoz.weebly.com/uploads/1/3/1/4/131407704/bafubesipalu-xivujezif.pdf
    • https://cdn-cms.f-static.net/uploads/4446264/normal_604d34ae15e5b.pdf
    • https://cdn-cms.f-static.net/uploads/4365653/normal_604d4d928a770.pdf
    • https://senemoribut.weebly.com/uploads/1/3/4/7/134703027/5320429.pdf
    • https://mobuwutibuw.weebly.com/uploads/1/3/0/7/130739624/fagerunig.pdf
    • https://sujixiku.weebly.com/uploads/1/3/0/7/130739139/3693607.pdf
    • https://cdn-cms.f-static.net/uploads/4369504/normal_60b7cabf1cafe.pdf
    • https://cdn-cms.f-static.net/uploads/4444882/normal_60595d5804471.pdf
    • https://cdn-cms.f-static.net/uploads/4374002/normal_6060c8e5dbc75.pdf
    • https://figiroxofidun.weebly.com/uploads/1/3/0/7/130740151/bbb97af8.pdf
    • https://static.s123-cdn-static.com/uploads/4386606/normal_5ff346657c834.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/a8564606-c09f-4151-a2f7-77c0fffa57aa/crowder_funeral_home_springfield_tn_obituaries.pdf
    • https://uploads.strikinglycdn.com/files/ccf2e78e-c888-4c87-a9ab-3f392cd1c9a7/81997013777.pdf
    • https://uploads.strikinglycdn.com/files/ac9445d5-6288-4ec3-9677-d347cca379de/how_can_i_download_clash_of_clans_on_my_pc_without_bluestacks.pdf
    • https://uploads.strikinglycdn.com/files/584b5493-4dca-4e4b-a076-1dcbde6714ba/sennheiser_ew_100_g4-835-s.pdf
    • https://uploads.strikinglycdn.com/files/aeeed6e6-9189-4934-b8da-3a9a3074d938/ocr_a_level_chemistry_topical_past_papers.pdf
    • https://uploads.strikinglycdn.com/files/6ff630f7-48ca-4a68-a31b-adeb8ae06e48/american_natural_history_museum_nyc_hours.pdf
    • https://uploads.strikinglycdn.com/files/c2e76698-4dd2-47f0-9c83-105d47dfee88/information_technology_salary_in_south_africa_2019.pdf
    • https://uploads.strikinglycdn.com/files/f3ee3107-caa7-4edc-885f-52aebce71601/fimitefesemukotu.pdf
    • https://uploads.strikinglycdn.com/files/b743a2a0-0aea-47e7-b20d-e2c827266755/71788707213.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e3c0.bin
1ab9f7a812ab4d2df8e96d7d750d3e9c95bf732c6d3563c198d0033f40a3a945
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3C0 5416 bytes
font_01_sfnt_off0000f62c.bin
ff4b9009663f764b78261578f735d3e27d86d3a86d7d60d6dc52d965043163d0
pdf-font-stream PDF embedded font (sfnt) at offset 0xF62C 10184 bytes