Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0e4a94146148d9d…

MALICIOUS

PDF

74.5 KB Created: 2021-03-30 22:31:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 175f4a8784727a682675c44603a1dd24 SHA-1: 1c90d8bf3119a48377b917142226f7b8f7c70d28 SHA-256: a0e4a94146148d9d769ff545cc6f24469dd5fe206650b7817e8baa53cc36e63f
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, identified as a link farm. This is supported by heuristics like PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM, indicating a malicious intent to manipulate search engine results or distribute further malicious content. The ML classifier and ClamAV detection strongly suggest maliciousness, with the primary attack pattern being the distribution of malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://golowaki.ru/award?keyword=epidemiologia+clinica+laura+moreno+altamirano+pdf PDF link annotation
    • https://nexakolaligu.weebly.com/uploads/1/3/1/8/131871479/9742757.pdfIn PDF document text
    • http://xivobivivupe.mygamesonline.org/bcom_computers_subjects_1st_year.pdfIn PDF document text
    • https://digafixi.weebly.com/uploads/1/3/0/7/130776371/e8a17.pdfIn PDF document text
    • https://kixofugowewo.weebly.com/uploads/1/3/1/8/131872146/2602741.pdfIn PDF document text
    • https://cdn.sqhk.co/vudupapuj/1Bgj8Z6/english_song_download_mp3_isaimini.pdfIn PDF document text
    • https://bikigevoxepasi.weebly.com/uploads/1/3/4/7/134716722/f021f213af23.pdfIn PDF document text
    • http://femuxeririta.mygamesonline.org/apokryphe_evangelien.pdfIn PDF document text
    • https://todilotifobaw.weebly.com/uploads/1/3/2/7/132712516/e0c376fb89b6fa.pdfIn PDF document text
    • https://cdn.sqhk.co/vuzefoveniri/gjzEzrW/bst_enterprise_timesheet.pdfIn PDF document text
    • https://cdn.sqhk.co/sojuzafu/ajbjeOV/e_news_vector_logo.pdfIn PDF document text
    • https://cdn.sqhk.co/bevizewo/EVNiehh/80367480232.pdfIn PDF document text
    • https://muxavitegujun.weebly.com/uploads/1/3/1/6/131637584/9154839.pdfIn PDF document text
    • https://derelegog.weebly.com/uploads/1/3/4/3/134339552/zudusox-mesilisamana-rakumi-letigonirama.pdfIn PDF document text
    • http://bomaduworofa.medianewsonline.com/40218096197.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://jazopizebe.atwebpages.com/23949218528.pdfIn PDF document text
    • https://a97cc435-ef8e-4ffb-8544-4b9c0bda5a6e.filesusr.com/ugd/7ab440_02c3493b1aa64bd9a27a7787999a765e.pdf?index=trueIn PDF document text
    • https://ed4d48c2-14ea-47f5-a89a-b82193587323.filesusr.com/ugd/8ce377_2784a9092d1f4dc9ba28c6fb2b57f439.pdf?index=trueIn PDF document text
    • https://30383b9b-b26a-44f4-9a26-03873af8f03c.filesusr.com/ugd/fdee49_6ede3510ae314237a5729a414d39f486.pdf?index=trueIn PDF document text
    • https://ba789de2-c385-43ee-b32d-a34c698d1993.filesusr.com/ugd/b7082a_da23a0ae581d4e359038d79c7ffb011d.pdf?index=trueIn PDF document text
    • https://538d8494-0c7d-401a-b890-0485f6bc7bca.filesusr.com/ugd/29c71c_beccd4cde0044632a9e356675bc497aa.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d555.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD555 5136 bytes
SHA-256: 3371820f1b71c10c8552721732947bc7b5e050ae8ec5453e8bfc47a09ab36256
font_01_sfnt_off0000e6b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B8 11624 bytes
SHA-256: 06fa637ca91c6fe4454c95ea2ba2e40b3716ab9ddf1164601e88a46c84f15d14
font_02_sfnt_off00010cac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CAC 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f