Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa362cbbf3f0d7c5…

MALICIOUS

PDF

93.4 KB Created: 2021-04-19 19:13:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: ac1c83778a6b1511dddda567ad31be7f SHA-1: 953acd5b7e0c4823b432a4581c77a6e6f455fffa SHA-256: aa362cbbf3f0d7c5dc2b1a83565b7e191750ceec4e8279c2711b058adceb371a
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, which is characteristic of SEO link farms or phishing campaigns. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan. The document body appears to be malformed or heavily obfuscated, preventing a clear understanding of its direct user-facing content, but the heuristic firings strongly indicate a malicious intent related to link distribution.

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://leonvi.ru/strik?utm_term=sunset+western+garden+book+tenth+edition PDF link annotation
    • https://cdn.sqhk.co/sajatanugeg/jwjjhju/timudebefakekesukemara.pdfIn PDF document text
    • http://dihtyar.online/tcp_ip_protocol_driver_service_missingubx06.pdfIn PDF document text
    • http://pixxel.life/xivetomijinexiramfpcuo.pdfIn PDF document text
    • https://cdn.sqhk.co/tosolizidovi/iHjbfhf/30165963694.pdfIn PDF document text
    • https://cdn.sqhk.co/xurajalijok/g6B95if/virog.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/02efffb6-3f84-4c8f-bb47-e49bc76bef35/vumaxulo.pdfIn PDF document text
    • https://e192e36c-395d-4660-9df6-aa7aed00c30a.filesusr.com/ugd/3aee12_cde593a8accc4665b9916b50d1be814b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b787f171-5267-4114-9aa0-349cf415a524/dns-323_firmware_1.09_download.pdfIn PDF document text
    • https://f4dd034e-00c7-465c-b850-fb2d75accad5.filesusr.com/ugd/769f78_930d7f7c151046a695a7a16c6487b6d1.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c6c2841c-f2f2-46e7-8b39-961ad6ee2517/danavobofo.pdfIn PDF document text
    • https://d934ed86-632c-4751-b35b-4303166f997e.filesusr.com/ugd/be0f55_af4c2d00b7fb46af81b7802814d71247.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/2ea06ab4-ba9d-453f-b4e4-1400bfb8d8e4/13499159510.pdfIn PDF document text
    • https://16e729f2-8c5c-4787-b670-14aeba6c5e03.filesusr.com/ugd/ac55e2_febd6438adef4430b4f0bc7564656910.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/295f8302-fbf3-4d82-8ddd-fb4254527a84/43604380125.pdfIn PDF document text
    • https://9b08d158-0e0f-4203-9b31-e1272d977b1c.filesusr.com/ugd/086daf_1c3314997098401aaf9117bb72e61dde.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/faddf4d3-c659-4cff-8d27-17d393d0d1c3/risepewojixofatepepi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/98226a6d-4855-4ff1-818c-4e481f6bd9a1/electrolux_central_vacuum_repair_locations.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bc874372-f121-4c26-b35e-66746ace8bde/rosatutigemejodilebe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f57cce4e-622f-4315-91a3-c83295c0dbcf/bikujowidefelur.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2c19fef2-c23d-4d7b-94a7-05490d90161a/katagejukemivola.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d04209ba-9878-4862-a824-879cfbfdf5d2/how_to_play_minuet_in_g_on_guitar.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_off00012e62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E62 5452 bytes
SHA-256: c3a0b539828621eaa038cb4f219b27e1f53d7f73a2526578f8d374666610994f
font_01_sfnt_off000140f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140F4 11376 bytes
SHA-256: f38dec02327e832cb51d4d2a206ed3535dc4b1d1995bb37ff55923aca957bcf5