Malicious PDF — malware analysis report

Static analysis result for SHA-256 36a291bda1340be3…

MALICIOUS

PDF

48.2 KB Created: 2020-08-19 00:04:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0a4e16618b21c29b6c8275585357c1c5 SHA-1: 194b707f030f505023fef5dd675dff5da42827d7 SHA-256: 36a291bda1340be3cc007c0d57f01a802fddc7ca46d0b3abff6a678c873f9212
152 Risk Score

Malware Insights

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

The PDF file contains multiple embedded URLs, with one identified as a malicious redirector. The document body, though heavily obfuscated, contains text referencing a 'resignation letter template' and the malicious URL. The heuristic firings confirm the presence of malicious redirector links and a link farm, indicating a phishing or redirection attempt. The ML classifier strongly supports the malicious nature of the 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.cc/pify?keyword=simple+resignation+letter+template+free
    • http://files.chrisrossarthur.com/uploads/1/3/1/1/131163932/17ea4e.pdf
    • http://files.shangrilacenterforhealing.com/uploads/1/3/1/4/131483317/6277764.pdf
    • http://rupap.palladinohomeinspection.com/uploads/1/3/1/4/131406717/3ce555912cccb.pdf
    • https://cdn.shopify.com/s/files/1/0429/2286/8892/files/functional_communication_training.pdf
    • https://cdn.shopify.com/s/files/1/0453/8961/1176/files/maxibemiponal.pdf
    • https://cdn.shopify.com/s/files/1/0437/9875/7538/files/autonomous_driving_system.pdf
    • https://cdn.shopify.com/s/files/1/0431/0132/3421/files/waldorf_curriculum.pdf
    • https://cdn.shopify.com/s/files/1/0433/8096/5534/files/89003402708.pdf
    • https://cdn.shopify.com/s/files/1/0431/2439/2087/files/22274291699.pdf
    • https://cdn.shopify.com/s/files/1/0433/8135/8759/files/bedingungsloses_grundeinkommen_vor_und_nachteile.pdf
    • https://cdn.shopify.com/s/files/1/0438/6340/8795/files/78538015985.pdf
    • https://cdn.shopify.com/s/files/1/0448/1217/3463/files/26720218418.pdf
    • https://cdn.shopify.com/s/files/1/0437/6294/2101/files/perimeter_and_area_worksheets_grade_6.pdf
    • https://cdn.shopify.com/s/files/1/0439/2786/3464/files/74053550902.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007a66.bin
3e719bca7774c0a19a6da1b925b1af363c4c87df38e58b14c5bb5696d6f6eeda
pdf-font-stream PDF embedded font (sfnt) at offset 0x7A66 5324 bytes
font_01_sfnt_off00008c64.bin
1fde71d97cea1f7fef07ff05bfea6364d5a848fc60d86cab3c2c798ea9e5199d
pdf-font-stream PDF embedded font (sfnt) at offset 0x8C64 12072 bytes