Malicious PDF — malware analysis report

Static analysis result for SHA-256 79a7a5d62ea8c436…

MALICIOUS

PDF

45.2 KB Created: 2020-10-19 11:56:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 54ea98b153926762a08b190fb15562ab SHA-1: 505f06a88022207f135d8f80fd7d92925da09933 SHA-256: 79a7a5d62ea8c436031c976fd95fc82b80d15c5faadad8ab6f0d8959460cea9f
184 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with one identified as a malicious redirector. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest this is part of an SEO link farm designed to drive traffic to malicious sites. The document body, though malformed, contains URLs that align with this finding.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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://gettraff.ru/123?keyword=thermodynamics+pdf+for+mechanical+engineering In PDF document text
    • https://cdn-cms.f-static.net/uploads/4366625/normal_5f875df05a6d6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368475/normal_5f8d02ca6905a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371800/normal_5f8d386d7429f.pdfIn PDF document text
    • https://rakamukomegu.weebly.com/uploads/1/3/2/6/132681656/ladefubit-tafojapumepokan-vowupe-zidedix.pdfIn PDF document text
    • https://rabugotekinevod.weebly.com/uploads/1/3/1/8/131871666/419cd37988.pdfIn PDF document text
    • https://rimesozarabef.weebly.com/uploads/1/3/1/6/131607712/zavababaxusi-vifuto-vobogiwev.pdfIn PDF document text
    • https://xojerajap.weebly.com/uploads/1/3/1/3/131384359/zebapesuluboxaj.pdfIn PDF document text
    • https://xumogimunosu.weebly.com/uploads/1/3/1/6/131607683/besosuror.pdfIn PDF document text
    • https://sakuvajavabese.weebly.com/uploads/1/3/1/3/131383602/2088346.pdfIn PDF document text
    • https://jakedekokobara.weebly.com/uploads/1/3/1/3/131381480/likanutavorolebonat.pdfIn PDF document text
    • https://ligofaxudatejot.weebly.com/uploads/1/3/0/7/130739538/77e93.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/cdb499d4-21e8-4c71-85c1-3aee0f1815fe/sudevinarosimolaripi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5e959c26-a390-431e-8aac-793cf80933bb/movixikusutumonesa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e8e5838b-099a-4e55-8d0f-3e060a7f2f62/calendario_2020_peru_con_feriados.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/31286612-015c-44bc-a136-2ada8f35811b/hoover_turbo_scrub_spinscrub_50_manual.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0461/8276/0601/files/heath_zenith_security_light_manual.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0484/3565/8906/files/midivuluruvasuse.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/9691/5616/files/brevard_county_termination_of_notice_of_commencement.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0479/0891/3319/files/northside_neighborhood_house_staff.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0500/2585/7181/files/danger_dash_mod_apk_game.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_off00006855.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6855 5620 bytes
SHA-256: dc7276dbab4aa317f3bf88f00e81aa110c396a34b2fb95d3720f9e9c320b36d0
font_01_sfnt_off00007b5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7B5B 14084 bytes
SHA-256: 83cb87b8bb06f09191424905e9e2e6af34299d41f7fbfc968e6f09e0b5e80ea3