Malicious PDF — malware analysis report

Static analysis result for SHA-256 18f820fa65c5b1e3…

MALICIOUS

PDF

87.0 KB Created: 2021-05-08 13:54:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 8884e79c5923ae41a89865aed63f1f8a SHA-1: d7f3a54f3607a1fc148f09f5afe961af004f74fa SHA-256: 18f820fa65c5b1e35394cbbb03cc787cef261d1d0fc37abc056a75b1d2387985
186 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by both ClamAV and an ML classifier. It contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO manipulation tactic. One of the embedded URIs, https://mezovuduw.ru/strik?utm_term=girl+boss+urban+dictionary, is likely a redirector to malicious content. The document body is heavily corrupted, preventing a clear understanding of its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://mezovuduw.ru/strik?utm_term=girl+boss+urban+dictionary PDF link annotation
    • https://zuwuroxiver.weebly.com/uploads/1/3/1/0/131070979/b009ef1d7ad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4462697/normal_601f6864881d5.pdfIn PDF document text
    • http://gutagige.sportsontheweb.net/developing_skills_for_the_toefl_ibt_intermediate_reading.pdfIn PDF document text
    • https://xojumemusip.weebly.com/uploads/1/3/4/0/134018475/5179c307187ac30.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376866/normal_606814f045614.pdfIn PDF document text
    • http://tofotibuwul.sportsontheweb.net/goredujebaku.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370525/normal_601a322e799fa.pdfIn PDF document text
    • https://cdn.sqhk.co/zalopubid/gjiizgh/vijofabifikowuva.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443357/normal_605517a36ac20.pdfIn PDF document text
    • https://kowexemi.weebly.com/uploads/1/3/1/8/131872048/76f500c67e.pdfIn PDF document text
    • https://cdn.sqhk.co/medujebukoma/ifUgcwm/99200889719.pdfIn PDF document text
    • https://cdn.sqhk.co/lexikegije/amghk3x/iron_sky_attack_squadron.pdfIn PDF document text
    • http://mubositesene.mypressonline.com/fajikusif.pdfIn PDF document text
    • http://jusojixanona.getenjoyment.net/samsung_wf210anw_xaa_specs.pdfIn PDF document text
    • https://dumejolizaxoko.weebly.com/uploads/1/3/0/8/130814858/3980770.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369916/normal_5ff3651a77a6b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4482849/normal_5fc76dedc2516.pdfIn PDF document text
    • https://wafodefa.weebly.com/uploads/1/3/4/4/134480145/2ba770f7b6fb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4502336/normal_60600eb26a106.pdfIn PDF document text
    • http://ferafukapawap.scienceontheweb.net/75008533688.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://vibirokudod.myartsonline.com/34945324964.pdfIn PDF document text
    • http://zowofiz.myartsonline.com/siras.pdfIn PDF document text
    • http://fugufaza.myartsonline.com/algebraic_expressions_formula.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f820.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF820 4972 bytes
SHA-256: 436458c17ac8d8d46093074d3aa8d04c676e740f04f8f3b81aa5a03d3395ea43
font_01_sfnt_off00010900.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10900 3484 bytes
SHA-256: 3fd1c57a422d527e7e3fc5dec232054f49a21c8ec9a5d2f9bfe4a58cd71f9fe4
font_02_sfnt_off000116ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116EE 11912 bytes
SHA-256: ba4928ae665422f3323208229b6523789f91177d62e4cfea16086f4b16d183e3
font_03_sfnt_off00013e65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E65 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f