Malicious PDF — malware analysis report

Static analysis result for SHA-256 318cd6348a3f3a69…

MALICIOUS

PDF

71.1 KB Created: 2021-03-26 10:35:39 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 89cefedd060faa6b094e6a4b2897a279 SHA-1: a424534e1890c8af6ee02265c0f699153bcc04a2 SHA-256: 318cd6348a3f3a69a491310e7695da122f0e670741639b341eb1a07d39d7a1a1
96 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating the presence of an external URI. The embedded URL, https://dafemum.ru/123?utm_term=ks3+maths+rounding+decimals+worksheet, suggests a phishing attempt, likely disguised as educational content given the URL parameters. No scripts were extracted, but the PDF structure itself facilitated the embedding of the malicious link.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://dafemum.ru/123?utm_term=ks3+maths+rounding+decimals+worksheet
    • http://vanlit.ru/674200612361o9xo.pdf
    • https://cdn-cms.f-static.net/uploads/4426960/normal_5fd62b87d692a.pdf
    • https://static.s123-cdn-static.com/uploads/4454990/normal_60090d0b27ff8.pdf
    • http://begemotiks.space/rorixarolilwbmt.pdf
    • https://cdn-cms.f-static.net/uploads/4415544/normal_605d97495a604.pdf
    • http://good-production17.site/evenflo_safemax_infant_car_seat_washing_instructionswgurg.pdf
    • https://cdn-cms.f-static.net/uploads/4454043/normal_604ed4915cdd0.pdf
    • https://cdn-cms.f-static.net/uploads/4475737/normal_601217c590437.pdf
    • http://mydenverneighborhoods.com/radio_top_40_uk3sbqh.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/dutimajizowa/87719140502.pdf
    • https://uploads.strikinglycdn.com/files/ffcc7372-d772-4d05-a141-d9800c421ade/xebagepulaxitobapi.pdf
    • https://uploads.strikinglycdn.com/files/5e60ab10-5650-4d08-8f15-41f07756a7ff/ruwewutuzosojosovuvu.pdf
    • https://s3.amazonaws.com/joterige/bt_hub_2_manual.pdf
    • https://s3.amazonaws.com/widuxade/google_map_api_sample_key.pdf
    • https://s3.amazonaws.com/luropi/st_bartholomew_s_school_newbury_uniform.pdf
    • https://uploads.strikinglycdn.com/files/1b585f3c-d823-4931-9ac1-6eab069843d3/killing_floor_2_character_tier_list.pdf
    • https://uploads.strikinglycdn.com/files/91852685-5165-44ed-a1a3-509e31a3d685/lavalitojunatevowijurumam.pdf
    • https://s3.amazonaws.com/simujix/15409529840.pdf
    • https://s3.amazonaws.com/xopugup/pepuwozinutijineteninet.pdf
    • https://s3.amazonaws.com/fejakixoweka/18910229600.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_off0000d6a9.bin
9d2edba5aeee163fe91e9303d12d33815c4dec011753afb2cff765d30799cc5f
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6A9 5644 bytes
font_01_sfnt_off0000e9be.bin
0b32d2236522aee1c21fd8129f53d9a221c2525967d189bdc6f606822f396249
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9BE 10428 bytes