Malicious PDF — malware analysis report

Static analysis result for SHA-256 caf777cede73b37b…

MALICIOUS

PDF

43.9 KB Created: 2020-08-08 03:30:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ce97c323acc4b3ac417b7b0b0b2ffd24 SHA-1: 78f8029c86a5e49a19ff1455d7ee2f51d7ce1cd7 SHA-256: caf777cede73b37bfd7e26254c05b4a8d2300cb78addb8f31c7736c697784ef4
152 Risk Score

Malware Insights

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

The PDF contains a deceptive document body masquerading as exercises, but it embeds a link to a known malicious redirector. The ML classifier strongly indicates maliciousness, and the presence of a link farm further supports a malicious intent to drive traffic to potentially harmful sites.

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.com/pify?keyword=achilles+tendinopathy+pdf+exercises
    • http://files.kellykeyboards.com/uploads/1/3/0/7/130775921/pakexovutu.pdf
    • http://files.katherienclairvoyant.com/uploads/1/3/1/6/131606330/fejupixapimoj_kukazotiwutamor_xivawowe_jogidizix.pdf
    • http://files.maltatenantsupport.com/uploads/1/3/1/0/131070313/d2b4523b.pdf
    • https://cdn.shopify.com/s/files/1/0432/0729/5140/files/61559783664.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/8011835234.pdf
    • https://cdn.shopify.com/s/files/1/0431/4647/7722/files/calendar_2020_malaysia_printable.pdf
    • https://cdn.shopify.com/s/files/1/0431/5214/6587/files/84504104846.pdf
    • https://cdn.shopify.com/s/files/1/0431/8032/7076/files/97245807331.pdf
    • https://cdn.shopify.com/s/files/1/0429/8915/8554/files/47792381836.pdf
    • https://cdn.shopify.com/s/files/1/0434/1448/7207/files/xafelibe.pdf
    • https://cdn.shopify.com/s/files/1/0430/6334/5301/files/lojavuwokoliwamoji.pdf
    • https://cdn.shopify.com/s/files/1/0428/2561/3475/files/lizom.pdf
    • https://cdn.shopify.com/s/files/1/0430/9850/5377/files/96843488957.pdf
    • https://cdn.shopify.com/s/files/1/0437/2099/9064/files/27782742747.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_off00006def.bin
528090d83941c87de2f52f327a64b7d55f6ceebe73a404fb9556f1e8c9e8d8d5
pdf-font-stream PDF embedded font (sfnt) at offset 0x6DEF 5400 bytes
font_01_sfnt_off0000805b.bin
9534257b74c4422ed3d5ef1039beeb95b1a4d1638a1f5d8f9895cb21689051e4
pdf-font-stream PDF embedded font (sfnt) at offset 0x805B 10120 bytes