Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b4af182209c9305…

MALICIOUS

PDF

90.2 KB Created: 2021-05-30 05:17:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: f4e66c69ae43b1588784dc6c76d1f2cb SHA-1: c1ff88326d4eed2c94bf662cf44b23353a9c8d59 SHA-256: 8b4af182209c9305f6972e2f017b9205339d75b1420c72690dc4398d11419a26
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable hosting, suggesting a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and external links are indicative of a phishing or malicious redirection attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://golowaki.ru/strik?utm_term=what+is+progress+notes+in+nursing PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4475737/normal_5fdbaf57014a4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501791/normal_601e70f26f28b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455176/normal_60125d3e6edf5.pdfIn PDF document text
    • https://borojiwanap.weebly.com/uploads/1/3/4/2/134235821/879f08.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4499282/normal_6032630492ff0.pdfIn PDF document text
    • https://gimeboxevamovuv.weebly.com/uploads/1/3/4/4/134494840/muledu-xoliwax.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414153/normal_601911e6a9618.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4428039/normal_6046de3f591a4.pdfIn PDF document text
    • https://fubotuvexar.weebly.com/uploads/1/3/3/9/133997611/suxox.pdfIn PDF document text
    • https://lijupumo.weebly.com/uploads/1/3/4/4/134496400/d22bb354ecc8c58.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409118/normal_60411d98eba4c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458839/normal_603ffb0fbf4fe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379034/normal_606e9710eb732.pdfIn PDF document text
    • https://pozewovuxawa.weebly.com/uploads/1/3/4/5/134592866/7938456.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451023/normal_602207cbe1686.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370989/normal_603bee5a5b0eb.pdfIn PDF document text
    • https://kovunigok.weebly.com/uploads/1/3/5/3/135317038/1b713b5cab.pdfIn PDF document text
    • https://tuxenovizomojow.weebly.com/uploads/1/3/7/5/137516496/4221102.pdfIn PDF document text
    • https://revejoduxu.weebly.com/uploads/1/3/4/2/134266419/90dd0240e53e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416671/normal_6024f4a06a460.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4483586/normal_5fe13f2131c26.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/bdb3395b-27c2-4e2b-a822-5c4737f14ff7/tegazusozobufatirumutij.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c9211f4e-0072-4747-9c90-7af2ba82ecf8/dinudifaliri.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4e3674b8-0d89-4ca9-b5f6-553ee8ea7149/cursos_de_ingls_en_new_york_manhattan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f53bad0d-aba8-44ba-9fee-2a2419b6985e/windows_server_2012_r2_antivirus_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/852699e8-c25f-433e-b232-6d348424fbb2/how_to_tell_if_dishwasher_float_switch_is_bad.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010714.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10714 7732 bytes
SHA-256: 86315600fbb0161728bfd9c4bd164cf02633946db13aec4735fa1be781540979
font_01_sfnt_off000120d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120D4 5064 bytes
SHA-256: 949fe35814221f7050896a17afe14da6ccb29c86df4f5c0e619c41c99f1ff26d
font_02_sfnt_off00013219.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13219 12168 bytes
SHA-256: b2d0cecc89f072cafc009f1564bc5f831378964fdd1479b2d9ccdf1451459f16