Malicious PDF — malware analysis report

Static analysis result for SHA-256 f843a4617f36e524…

MALICIOUS

PDF

83.0 KB Created: 2021-03-29 14:35:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 4dc2b121812ff0390c9e9cd965129714 SHA-1: 74b634998786fcf3bec39955f2e3fa8370a750ef SHA-256: f843a4617f36e524f79e40ee3a59da6116ac127bb50a47d97c29ab94a05e9159
126 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • 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://druttle.ru/award?keyword=qualitative+research+data+analysis+pdf PDF link annotation
    • https://viremekim.weebly.com/uploads/1/3/1/4/131407965/kitunepepuwa-luzodozeni.pdfIn PDF document text
    • https://nifevokore.weebly.com/uploads/1/3/1/4/131437532/dozepoxanidob.pdfIn PDF document text
    • https://tamoxukezoge.weebly.com/uploads/1/3/4/5/134585929/gagobafopabe_murol_kelado.pdfIn PDF document text
    • https://cdn.sqhk.co/gapekozuwa/eRE0igS/wozepoxemukekow.pdfIn PDF document text
    • https://pozanabuloga.weebly.com/uploads/1/3/4/3/134366917/6a34e.pdfIn PDF document text
    • https://cdn.sqhk.co/tirinakiweda/duggFii/power_media_player_evoparser_version_conflict.pdfIn PDF document text
    • https://cdn.sqhk.co/rejiwosujupa/ajgICke/jacksonville_beach_surf_report.pdfIn PDF document text
    • https://cdn.sqhk.co/wetabupi/giWp3gh/can_you_escape_room_2_level_14.pdfIn PDF document text
    • https://zalawevovupat.weebly.com/uploads/1/3/0/9/130969727/zabikidituziponufuku.pdfIn PDF document text
    • https://mugakosi.weebly.com/uploads/1/3/1/3/131379948/03d1e11407a25.pdfIn PDF document text
    • https://nozijuga.weebly.com/uploads/1/3/4/6/134698325/wulipikelejuwop.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
    • https://uploads.strikinglycdn.com/files/1d85d0e8-467c-46f1-b16f-39379a8dbcfd/bofoladopadakijemefinap.pdfIn PDF document text
    • https://c7bff75e-0a19-4817-9d47-fca4cf08161b.filesusr.com/ugd/3b6424_7205c8523cfa43b8b94cd479d569a2ed.pdf?index=trueIn PDF document text
    • https://64db0a9d-d2b7-4705-beb9-75cca7f1d068.filesusr.com/ugd/4c6241_c86e70e17b424fa59e817ef8be9cf371.pdf?index=trueIn PDF document text
    • https://f733e552-90a1-4d1f-83ca-a6b36afcf31c.filesusr.com/ugd/38bf1f_5c1e1c9806194f00bbc7de82fcdb2292.pdf?index=trueIn PDF document text
    • https://86a9da1b-0b57-4b35-a77a-523886b904cd.filesusr.com/ugd/0d9a50_d6994b707bed4be89c84b6ee07165dd0.pdf?index=trueIn PDF document text
    • https://54570836-76ea-4100-b78f-d1ba4c3cc0d1.filesusr.com/ugd/21ac59_a5a159e7ee734ce39d202963875d5741.pdf?index=trueIn PDF document text
    • https://ea29520f-fefa-4c12-ab21-0e0839e82572.filesusr.com/ugd/5d2047_1ca20da88dd6464fab3c160be617ff6c.pdf?index=trueIn PDF document text
    • https://41c240d9-b4af-4f88-8fa4-2a41cce3a287.filesusr.com/ugd/01bc73_1677a02909524edaa27ae5a973728166.pdf?index=trueIn PDF document text
    • https://2d130471-2a64-48ba-87cf-8f1e86c6acad.filesusr.com/ugd/9c43ec_10944141cb8b4ac883708067c253d9c6.pdf?index=trueIn PDF document text
    • https://96daf755-36ed-4ece-a185-bed8db3f70ea.filesusr.com/ugd/a95cda_e7f32e8cd27d42f6a119566d914807de.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/aa39a4ae-3e23-4214-b32e-9b246efff095/oppo_bdp_103_firmware_update.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f776.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF776 5236 bytes
SHA-256: 1e3ea326ded9e41a41e6594cc597d61c51566e40ccbbb01e1ffec604de9498f7
font_01_sfnt_off00010943.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10943 11432 bytes
SHA-256: f87205fdec32dd8eed8ad9fc8d9169fb38e69b22f2e8d169cb5403912782acfe
font_02_sfnt_off00013018.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13018 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34