Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb028da7a7073bd2…

MALICIOUS

PDF

75.5 KB Created: 2021-04-05 22:45:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: c21f49a04c98cf9dab84489145a360d2 SHA-1: 77e6c2deee03c7583f563fad52760d18f8705ee2 SHA-256: bb028da7a7073bd2ecea3c9976beebf475f2bb35baba6e16b41d39ec3e66e338
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting, indicating a link farm or SEO spam operation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards malicious content designed to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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.
  • 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://jacksth.ru/award?keyword=huduma+number+form+pdf PDF link annotation
    • https://ruwijupoxotafan.weebly.com/uploads/1/3/0/8/130814308/76de1ed1.pdfIn PDF document text
    • https://padixegidenu.weebly.com/uploads/1/3/1/1/131164435/9928360.pdfIn PDF document text
    • https://cdn.sqhk.co/lilodipu/1sJijpE/u20_rugby_world_cup_2015_fixtures.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4423145/normal_60470a40c824d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4392237/normal_60160088c77fe.pdfIn PDF document text
    • https://cdn.sqhk.co/nejibija/hEjiahj/35646363103.pdfIn PDF document text
    • https://nogulakotu.weebly.com/uploads/1/3/0/9/130969216/toxekij.pdfIn PDF document text
    • https://xixolediz.weebly.com/uploads/1/3/4/5/134513169/sisumoz-pufumu-zibukez-muvudapire.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/0549afca-5932-4cb6-b772-f1c26d73567c/the_rules_of_basketball_for_beginners.pdfIn PDF document text
    • https://fe2b84af-b373-48e0-a714-f820169e3fe9.filesusr.com/ugd/ed1d2e_e8eef425222d442a936445d66be1768f.pdf?index=trueIn PDF document text
    • https://cf176ec6-4820-456b-adf9-61e5f06c968f.filesusr.com/ugd/43d598_b40a5be0c16e4f70b8f57c87e9e5ca19.pdf?index=trueIn PDF document text
    • https://146c8b6c-0b46-450b-8ed0-b45f1e2a4974.filesusr.com/ugd/b58d21_9c5ba2903f3a4c8a961e56c2d3387004.pdf?index=trueIn PDF document text
    • https://f18b8dc1-3ce9-44bd-8712-01435d039869.filesusr.com/ugd/b97cba_2b7f9ad3e047481f9e729baeeaadcb1b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/579d5ac4-3d78-4f80-9dde-c7e809b43520/how_to_get_my_armitron_watch_off_military_time.pdfIn PDF document text
    • https://356bbf58-84af-4bff-99a9-d03346e46411.filesusr.com/ugd/b5472a_5f71f0f9046443419430ac7a7e331e15.pdf?index=trueIn PDF document text
    • https://584abdf6-e408-48d3-a53c-4313a8f82471.filesusr.com/ugd/18ee90_d7dfbb0f2abd4339a3d02f9a60daf506.pdf?index=trueIn PDF document text
    • https://e50eee24-2d95-422d-8083-6f618d95927b.filesusr.com/ugd/594ae5_60fe886c6674476ca65937c872a5d1c4.pdf?index=trueIn PDF document text
    • https://12dd324c-696b-4d67-8c19-991f3eacec2c.filesusr.com/ugd/eeb7bd_8ab13e9fbd9d4f08b83cae0a3f6de6df.pdf?index=trueIn PDF document text
    • https://e192e36c-395d-4660-9df6-aa7aed00c30a.filesusr.com/ugd/3aee12_7a34584370e64f0da2da09aabadf8646.pdf?index=trueIn PDF document text
    • https://f7cac2f2-528f-490f-9bef-cb2448a877de.filesusr.com/ugd/529ba0_f5170b4593bc42298813d72438effade.pdf?index=trueIn 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_off0000ea8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA8F 5076 bytes
SHA-256: 9db9ec08095264f62ade1327f9530dd1998f34f622f1dd6fbd09aba06eabd719
font_01_sfnt_off0000fbb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBB4 11008 bytes
SHA-256: 8941e953794b1a0ea16d94784fc16f1427669ce8f8e476c456f3c977f8c3bc85