Malicious PDF — malware analysis report

Static analysis result for SHA-256 92c45de11061dfbe…

MALICIOUS

PDF

80.7 KB Created: 2021-05-29 14:41:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dca74f3f06f4f079ceac6b4d2b516317 SHA-1: 0e33d3d9c97afd9b0eeb3f2861f9b18b413a3124 SHA-256: 92c45de11061dfbe03cef2b8713fef94e003b3b02814d6d6df0315e3d1031bbd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file is identified as malicious by multiple heuristics, including a critical ClamAV detection and an ML classifier. It exhibits characteristics of a PDF link farm, containing numerous external links, one of which is to zajinet.ru. The document body is heavily obfuscated and appears to be a lure related to an 'alkaline diet list printable'. The presence of embedded external links suggests an attempt to redirect users to potentially harmful content or for SEO manipulation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://zajinet.ru/wb?keyword=alkaline%20diet%20list%20printable
    • https://static.s123-cdn-static.com/uploads/4415782/normal_5fe49a07c2d2d.pdf
    • https://static.s123-cdn-static-d.com/uploads/4411483/normal_60aff8d1241ad.pdf
    • https://cdn-cms.f-static.net/uploads/4483070/normal_6042f4a228108.pdf
    • https://static.s123-cdn-static.com/uploads/4449984/normal_5ffed4f098731.pdf
    • https://peworiwuka.weebly.com/uploads/1/3/4/6/134693567/9704225.pdf
    • https://sajolunuweto.weebly.com/uploads/1/3/1/4/131407571/lever.pdf
    • https://bejazono.weebly.com/uploads/1/3/5/3/135315558/3977a3482deb5.pdf
    • https://malubolowogen.weebly.com/uploads/1/3/7/5/137506398/kiwavupo-tasiwonivezozot-lubonedaxobudi-wajiwevetojavow.pdf
    • https://static.s123-cdn-static.com/uploads/4409811/normal_5fc88021c5523.pdf
    • https://static.s123-cdn-static.com/uploads/4412900/normal_5ff683a9a06a3.pdf
    • https://cdn-cms.f-static.net/uploads/4421208/normal_601430dc95cfb.pdf
    • https://dewotime.weebly.com/uploads/1/3/1/6/131606762/pozigi_rimarop.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/df1a5c8a-32ea-4cdf-aee0-6ff903c71bfe/xokokokobubojagovami.pdf
    • https://uploads.strikinglycdn.com/files/bc68e0d4-7776-4a99-be4a-f5bcbfb936a0/exam_ref_70-483_programming_in_c_2nd_edition_free_download.pdf
    • https://uploads.strikinglycdn.com/files/ec44c88f-f82f-436c-b12b-1713a73d6f93/93259953113.pdf
    • https://uploads.strikinglycdn.com/files/8801ead0-53d1-474a-9dcf-e96bb5bd09c2/90551011901.pdf
    • https://uploads.strikinglycdn.com/files/23e3fb86-c9c5-4195-bae8-f034f1528ea6/what_is_combining_like_terms.pdf
    • https://uploads.strikinglycdn.com/files/212fb5d4-6b25-496d-b09d-671ec7c3ba34/song_of_solomon_8_7_meaning.pdf
    • https://uploads.strikinglycdn.com/files/318224ae-b81d-491d-b7fa-4821d83242d0/dikujinakabovaka.pdf
    • https://uploads.strikinglycdn.com/files/82470cbd-f738-4155-b3f0-fb28caee30f6/lafometi.pdf
    • https://uploads.strikinglycdn.com/files/4d0b72c6-74e1-4a17-a762-ee236e36f85e/narrative_writing_samples_grade_6.pdf
    • https://uploads.strikinglycdn.com/files/a674cfbd-b321-4ddf-9332-c63508a5409c/canon_xh_a1_3ccd_hd-camcorder.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ff55.bin
63a659bda31bda822b5dc0161dfc54701a71932b913fd3f786098083cb6c5435
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF55 5148 bytes
font_01_sfnt_off000110dd.bin
c31c40a082b8745061c77c753846c130cfec7e0414b5d4124c7af63c1e7562b6
pdf-font-stream PDF embedded font (sfnt) at offset 0x110DD 10804 bytes