Malicious PDF — malware analysis report

Static analysis result for SHA-256 4df7d04e2426a449…

MALICIOUS

PDF

74.6 KB Created: 2021-02-22 11:25:51 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 2765f0741bf87adf2537a20c4c6d2fd0 SHA-1: 21b29e5685e138b9942a659330a238b98f236acc SHA-256: 4df7d04e2426a4496190925b090e06bb0c388c40ef809361c9fba7c368755eb2
186 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, indicating it functions as a link farm. This is strongly suggested by the 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristics. The ML classifier and ClamAV detection further confirm its malicious nature, likely for phishing or SEO spam. The embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://leonvi.ru/strik?utm_term=are+arms+attractive PDF link annotation
    • https://cdn.sqhk.co/bidelefo/hhnbYvT/subway_customer_service_phone_number_uk.pdfIn PDF document text
    • https://wovasemuzusalej.weebly.com/uploads/1/3/1/6/131636629/129e7599.pdfIn PDF document text
    • https://xopoloxunevagig.weebly.com/uploads/1/3/1/4/131406528/28d6f8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451018/normal_602305765149f.pdfIn PDF document text
    • https://xedijekotaz.weebly.com/uploads/1/3/1/6/131606072/vinonerabuv.pdfIn PDF document text
    • https://lubozukutiximik.weebly.com/uploads/1/3/4/4/134472848/pazetuzesotatuj.pdfIn PDF document text
    • http://artyom.guru/55333361975pul1r.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451940/normal_602eae3e0dae3.pdfIn PDF document text
    • https://buzubexod.weebly.com/uploads/1/3/4/0/134017192/ccb1af7d41db2.pdfIn PDF document text
    • https://cdn.sqhk.co/ruwonumatag/ehjjjBz/battlelands_royale_skins_hack.pdfIn PDF document text
    • http://irisca.online/horn_of_winter_game_of_thrones_show36kpo.pdfIn PDF document text
    • https://tatisosef.weebly.com/uploads/1/3/5/3/135333589/balekaka_wipemizafesimon.pdfIn PDF document text
    • https://cdn.sqhk.co/lokalofobox/dulZvhj/moto_g_power_review_pcmag.pdfIn PDF document text
    • https://wurewoji.weebly.com/uploads/1/3/1/4/131438788/mibikipokabewigetite.pdfIn PDF document text
    • http://donbetosstreettacos.com/highway_bike_rider_3d_race63jsi.pdfIn PDF document text
    • http://titoto.xyz/425422330657d7zf.pdfIn PDF document text
    • https://cdn.sqhk.co/xasurila/qieTVid/houston_bcycle_promo.pdfIn PDF document text
    • https://vutameko.weebly.com/uploads/1/3/4/5/134576445/xajisibe_rijuwadezajejes_faxebos_gekatuvi.pdfIn PDF document text
    • https://sojofiveku.weebly.com/uploads/1/3/1/6/131637763/a4797b064a64e.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/tevigotu/19793101740.pdfIn PDF document text
    • https://s3.amazonaws.com/pizivurapab/ditokaki.pdfIn PDF document text
    • https://s3.amazonaws.com/genedesowul/farmacologia_de_autacoides.pdfIn PDF document text
    • https://s3.amazonaws.com/nasitevu/letter_from_birmingham_jail_annotated.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_off0000e6a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6A0 4964 bytes
SHA-256: 70516f415fbf84079d0699a54ffbb952a26a7a18e29c10006ecfd8565a73f14f
font_01_sfnt_off0000f772.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF772 11020 bytes
SHA-256: 8a47772c3c0b372796330905a9c6b5d2b8c05af1698b59249a125dc5b8fddf63