Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a2b9f2dc2b30971…

MALICIOUS

PDF

108.1 KB Created: 2021-03-17 06:15:34 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: a4ad368602a6b237fc76708ad2ac899a SHA-1: 4d6f75b8d113695c52c162f37e7356f33cf4d1f5 SHA-256: 3a2b9f2dc2b3097177d8dce8be5770116d79994634c13cddffad85461627495f
244 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical finding for linking to known malicious redirector infrastructure. The document contains a large number of embedded URLs pointing to various PDF files, suggesting a link farm or phishing campaign. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/123?utm_term=watusi+apk+iphone In PDF document text
    • https://cdn.sqhk.co/xajevedu/hdKoTLj/30873709091.pdfIn PDF document text
    • https://cdn.sqhk.co/merebiwisux/hbhejhO/10882390746.pdfIn PDF document text
    • https://zubisixoligifi.weebly.com/uploads/1/3/4/4/134479514/fdf2a0f47cfd22.pdfIn PDF document text
    • https://cdn.sqhk.co/budajawisore/eigGhag/labijolukupolij.pdfIn PDF document text
    • https://zororoxuz.weebly.com/uploads/1/3/4/3/134309160/174051.pdfIn PDF document text
    • https://cdn.sqhk.co/womawuxinuge/hjTjgzs/ninediriwigevoxuxela.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446390/normal_6048c97284dc4.pdfIn PDF document text
    • https://cdn.sqhk.co/mimofeto/Lyhdhil/tamil_album_audio_songs_free_starmusiq.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386620/normal_60246c106c6aa.pdfIn PDF document text
    • https://cdn.sqhk.co/livefivepa/5Mieiig/14524540740.pdfIn PDF document text
    • https://zonujonuwug.weebly.com/uploads/1/3/4/3/134309714/jewafireg-sowes.pdfIn PDF document text
    • https://cdn.sqhk.co/baxoladipezu/gi9KghB/injustice_gods_among_us_xbox_one_gameplay.pdfIn PDF document text
    • https://vesasasafej.weebly.com/uploads/1/3/4/7/134758359/radevofupiz_susuladegidatan_xesovugi.pdfIn PDF document text
    • https://cdn.sqhk.co/vonirosidejo/dhaAg5F/xbox_beta_installer_stuck_on_making_things_awesome.pdfIn PDF document text
    • https://zobatovegu.weebly.com/uploads/1/3/0/8/130873738/topuvejaserumun-wemokadid.pdfIn PDF document text
    • https://cdn.sqhk.co/nidebuwe/h2uhhhd/zurabaxufodubegoxe.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4463810/normal_5fcabe8a4a7ad.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off00016b9e.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x16B9E 31844 bytes
SHA-256: c9f1094037fff6056d72c804713070b213cb4b778b0ef40cfad25311b895e8ef
font_00_sfnt_off0001391d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1391D 4856 bytes
SHA-256: e7ae8b65120ba7fd8d525c9ddb8f8fc1c7331174136d80a458f97669597a5958
font_01_sfnt_off000149b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149B1 9828 bytes
SHA-256: 769a9d2636be9a6e534e70c96ba050ad217ef360f979bb9f3910b59ffaf2821c