Malicious PDF — malware analysis report

Static analysis result for SHA-256 c937c94b313cbe32…

MALICIOUS

PDF

51.5 KB Created: 2020-10-28 17:16:39 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-31
MD5: 6682bfe979bdca19af8d04c353d5df2f SHA-1: 5b7d70eb79572cb25d26719d919b7577bcfd5004 SHA-256: c937c94b313cbe32cb726f007910847241f95108a3212f148ff05070ff763cd8
184 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to disposable hosting and redirector infrastructure, indicating a link farm designed to lure users to malicious sites. One critical heuristic identified a link to known malicious redirector infrastructure, and the ML classifier strongly flagged the PDF as malicious. The document body, though heavily obfuscated, contains references to the malicious URL and other PDF links.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://cctraff.ru/strik?keyword=nevada+family+law+practice+manual In PDF document text
    • https://cdn-cms.f-static.net/uploads/4413118/normal_5f96da92de6ff.pdfIn PDF document text
    • https://genigudepa.weebly.com/uploads/1/3/1/0/131070712/4e0d994f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369324/normal_5f98f711ab245.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365626/normal_5f8b7db07720a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380237/normal_5f8b6de4245a4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365570/normal_5f876db3462f8.pdfIn PDF document text
    • https://buveziketi.weebly.com/uploads/1/3/1/3/131398526/cbe19d58fc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383460/normal_5f8c61f7c7d94.pdfIn PDF document text
    • https://tevitoretej.weebly.com/uploads/1/3/2/6/132680933/fotibakebatukijageje.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371003/normal_5f894117e6d78.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367912/normal_5f8af62b56280.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414488/normal_5f94d4234c710.pdfIn PDF document text
    • https://walinakonefal.weebly.com/uploads/1/3/4/3/134316097/7639137.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374024/normal_5f8fcde1223b1.pdfIn PDF document text
    • https://bizetuxerupa.weebly.com/uploads/1/3/0/8/130873791/fatitadajix.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://cdn.shopify.com/s/files/1/0268/7841/0942/files/alternator_working_principle_in_tamil.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/1270/1854/files/jawbone_jambox_manual_pairing.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0492/7756/7132/files/gallery_lock_software_for_android.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dbac45aa-66d0-4aea-a15b-234cd839caaf/sosuxutolumefaj.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8de2ae06-b06b-4204-aa28-52a126ec1451/48008206772.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9877f849-0f92-4fe5-ae44-73f02dbfac33/43398336270.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0482/9341/3025/files/is_west_coast_capitalized_ap_style.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/8567/6188/files/android_aosp_keyboard_source_code.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0436/3000/2336/files/medieval_total_war_2_cheats_princess.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/52ba2797-6097-454c-96b1-8197888821b1/hp_photosmart_6520_printer_instructions.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_off00007cdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7CDF 5116 bytes
SHA-256: 066279924fdf0f9d9f3435046305c6ee8c9346e55f1a1c23b9581d6ed72187fa
font_01_sfnt_off00008e50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8E50 10732 bytes
SHA-256: 63aa6a6379937096aef442052b3c27bf195693fe1f46ae2038250a9151f82086
font_02_sfnt_off0000b266.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB266 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333