Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c4b8158ade0ebc0…

MALICIOUS

PDF

78.7 KB Created: 2021-04-07 19:25:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 1fc415793b37beb3774495fd23995948 SHA-1: 28b0cc9ffdd1b39c0d025410682cb77b8795d200 SHA-256: 1c4b8158ade0ebc0667a3eaea2632940f3e1fdeae80bac62d4c7b9d8f8b41688
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to numerous external URLs, one of which is `https://resalured.ru/123?utm_term=mhra+guidelines+for+computer+system+validation`. This suggests the document is likely used for SEO spam or phishing, attempting to drive traffic to potentially malicious or deceptive websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://resalured.ru/123?utm_term=mhra+guidelines+for+computer+system+validation PDF link annotation
    • https://cdn.sqhk.co/powitaxixu/jicuijK/pasarunad.pdfIn PDF document text
    • https://cdn.sqhk.co/vumuwuxa/csJhc6A/planet_of_the_humans_documentary_trailer.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413474/normal_60206d7720e2c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417321/normal_5fd7f29f07996.pdfIn PDF document text
    • https://cdn.sqhk.co/poxirowo/4k19hb8/painting_house_exterior_colour_ideas.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4488315/normal_5fc91bb881c20.pdfIn PDF document text
    • https://cdn.sqhk.co/jesovolavig/jijghhb/tukukolororalobis.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415534/normal_606dcdf5422ca.pdfIn PDF document text
    • https://cdn.sqhk.co/nalawanuxa/JidibNp/6797009821.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427781/normal_5fdbacd0ad4ed.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386597/normal_5fe98ff6c82e7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473645/normal_6019821382bdb.pdfIn PDF document text
    • https://cdn.sqhk.co/gikunixa/RieGjed/free_slot_casino_games_online_for_fun.pdfIn PDF document text
    • https://cdn.sqhk.co/ronofumito/xgjeji3/monument_valley_utah_hotels.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4457011/normal_5fc5b56535b61.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417817/normal_6051adc8bff15.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://b20aee1f-b1b7-4e4e-be5e-d884e4ece670.filesusr.com/ugd/10e3af_b9b3b53e48134ac2a53d35f000e1b5f3.pdf?index=trueIn PDF document text
    • https://6c403777-3bdb-430d-a4ca-23d5788374d5.filesusr.com/ugd/e0034b_98c5d96499fd4bfe96635685e7d6fb4d.pdf?index=trueIn PDF document text
    • https://e0220c8c-c322-4c33-af83-7c5b0fe00b66.filesusr.com/ugd/a771bd_55adfdfca8e440358dd209c69b22ed45.pdf?index=trueIn PDF document text
    • https://348ddb29-83e1-4812-94a1-743b72ef9b42.filesusr.com/ugd/23b571_c3b44bec577544ff8dc6ab50e9e6832d.pdf?index=trueIn PDF document text
    • https://5fa60de5-32ab-41ac-ba65-77330e21e623.filesusr.com/ugd/2e16aa_4cd07dc4d7684863b8df139871dedce1.pdf?index=trueIn PDF document text
    • https://11ca5eb4-0abe-4d5d-8073-3f36f6088e80.filesusr.com/ugd/8b62d8_d5d6046a75ae4adb8d361d480319d9c1.pdf?index=trueIn PDF document text
    • https://cc46d2ba-e7cf-42f8-aa62-b015a0c17ef0.filesusr.com/ugd/d180c3_928cfab1c8da4d38b0025da745f2d876.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_off0000f5f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F5 5736 bytes
SHA-256: 19584d5a91b8728cdcb9f8ed520253f507b6e3726b360ea964922c58fc81ab0b
font_01_sfnt_off00010973.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10973 10536 bytes
SHA-256: 599f984f0f43f816369587964389ddc727e9a3867a092419707416560cfc82b7