Malicious PDF — malware analysis report

Static analysis result for SHA-256 c681fe2c03fe9f03…

MALICIOUS

PDF

68.2 KB Created: 2020-08-20 11:00:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ceb3ec0d43c27648481d393fbb82c417 SHA-1: 31d584b04a0f8a837e60dadf674c6413947048ab SHA-256: c681fe2c03fe9f03ccca0d3b6cd25c2786b33379d72cb7220f69fc8de38286cf
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to a redirector service (ttraff.ru) known for malicious activity. The document body, though heavily obfuscated, also contains the same malicious URL, suggesting an attempt to drive traffic to potentially harmful content. The ML classifier strongly supports the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • 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://ttraff.ru/pify?keyword=bernette+65+sewing+machine+manual
    • http://files.classicalballetofmd.org/uploads/1/3/1/0/131070983/nekaz.pdf
    • http://files.corneliusmullerproductions.com/uploads/1/3/1/1/131164231/fazoga.pdf
    • http://files.cogopsa.org/uploads/1/3/0/8/130813528/zokesaxajewakofetebo.pdf
    • https://cdn.shopify.com/s/files/1/0429/5114/7679/files/65368689442.pdf
    • https://cdn.shopify.com/s/files/1/0450/4656/2966/files/weigle_2020_assessing_writing.pdf
    • https://cdn.shopify.com/s/files/1/0434/8307/0630/files/xamorova.pdf
    • https://cdn.shopify.com/s/files/1/0432/9163/9974/files/dallas_fort_worth_airport_map.pdf
    • https://cdn.shopify.com/s/files/1/0428/9029/7507/files/66815918181.pdf
    • https://cdn.shopify.com/s/files/1/0438/3545/7696/files/mother_3_translation.pdf
    • https://cdn.shopify.com/s/files/1/0430/0341/2633/files/clinical_examination_talley.pdf
    • https://cdn.shopify.com/s/files/1/0430/4489/6925/files/44115616021.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/

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000a84b.bin
28040654355a503bc5fed249472ae68f76acae8e473d5caec0f52cf7ea5dc745
pdf-font-stream PDF embedded font (sfnt) at offset 0xA84B 5404 bytes
font_01_sfnt_off0000ba86.bin
9566c561863198e01970a0f87e27e9f9deda09d4d6b34b18e17a2b7ac81a4ea0
pdf-font-stream PDF embedded font (sfnt) at offset 0xBA86 2108 bytes
font_02_sfnt_off0000c3af.bin
fd0f3f38b489eef563898a4a5ae4183b31e08cefe7b428e778f7143742120944
pdf-font-stream PDF embedded font (sfnt) at offset 0xC3AF 16472 bytes
font_03_sfnt_off0000f5ea.bin
cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5EA 4324 bytes