Malicious PDF — malware analysis report

Static analysis result for SHA-256 b036fbec9e6ad601…

MALICIOUS

PDF

71.8 KB Created: 2021-04-13 01:24:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: f23c21d7b6a2b845b9353dd34c30ff6b SHA-1: 22f32500a90bd4a3179ea15eb8077340470a8124 SHA-256: b036fbec9e6ad6011c25835640f412e1f4ac814f8e3d897102f21fe2310bc405
126 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, identified as a link farm. The primary malicious intent appears to be directing users to potentially harmful content hosted on disposable domains. The ML classifier strongly indicated maliciousness, and the presence of numerous SEO-related links suggests an attempt to manipulate search results or distribute malware indirectly.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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.
  • 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://mezovuduw.ru/strik?utm_term=mechanical+engineering+drawing+pdf+book PDF link annotation
    • http://lightly.store/english_placement_test_oxfordcrvpl.pdfIn PDF document text
    • https://cdn.sqhk.co/savaketiju/41dXFcD/injustice_2_legendary_edition_characters_not_available.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417675/normal_5fe9d8ced4061.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4497131/normal_60407af499e43.pdfIn PDF document text
    • https://cdn.sqhk.co/neganobasiwe/giCN4gf/pomutorakovizezi.pdfIn PDF document text
    • http://summerita.fun/pathfinder_character_sheet_fillablec7w8s.pdfIn PDF document text
    • https://cdn.sqhk.co/towafeniruje/hguidL1/warlock_dawnblade_flying.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479445/normal_606e48447630c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4408464/normal_5fcafa992b176.pdfIn PDF document text
    • http://levantemosaic.com/wugosexomefebaliwon0bn1.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/948915c6-f0fb-456b-9479-45dac9157462/41274150959.pdfIn PDF document text
    • https://1e1f235d-56dd-4976-b20d-d38e3fe7b172.filesusr.com/ugd/210b45_1c2deff2c65f4e6fa72e4487d5f6ecd8.pdf?index=trueIn PDF document text
    • https://ca30e0e0-ecf2-44ab-b6a2-fe26291458be.filesusr.com/ugd/34e21e_0906eab98b394ad7b9bb3df12f9b8c51.pdf?index=trueIn PDF document text
    • https://e0220c8c-c322-4c33-af83-7c5b0fe00b66.filesusr.com/ugd/a771bd_ed87c6de6d2b4e8181320b5d40305bde.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/bcf97671-c9e1-4312-a529-1d8d4298204b/cyrano_de_bergerac_movie_actors.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e4b30c51-158c-43e2-a050-3392e38a1907/sojekawadakibilifewazo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/77742b30-aa9e-4ad3-a158-ce89d1b32dbe/couples_bible_study_plan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/50186071-726a-4aa7-a06f-f4636d190e0c/tirukeromefigotuze.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8c3cfcef-4b1f-43b5-b37e-be9a1970c866/95985618008.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/88843945-c81d-4e22-b1ee-015b44236adc/25612726178.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a2699350-64ea-4bb9-97d3-3e8a157cd9b4/cuales_son_los_30_derechos_humanos_de_la_onu.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_off0000db32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB32 5540 bytes
SHA-256: 54e467693d598c4ed28af144dc3f65137cc530d5cc832a56c4ecd2d56e8b0135
font_01_sfnt_off0000ee24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE24 10568 bytes
SHA-256: 8e1e1c9d17999f3512b913ef5df2f5977a0dffa5f76083c881a57e0dbf46de37