Malicious PDF — malware analysis report

Static analysis result for SHA-256 cbc0ead937f7a5c5…

MALICIOUS

PDF

49.0 KB Created: 2020-08-22 09:26:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cc37c612e183453341cb9f0e7a0d7d71 SHA-1: 32f7729ed58f82c0f638a37fd8745bfe43a48705 SHA-256: cbc0ead937f7a5c5273cb4910d8cb85137f7e84995d933d3a176e17a8c5db72f
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic firing for a malicious redirector. The primary URL, 'https://ttraff.com/pify?keyword=cover+letter+template+structure', is flagged as malicious. The document also exhibits characteristics of a link farm, with many links pointing to Shopify domains, likely to obscure the malicious intent. The ML classifier strongly supports the malicious verdict.

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=cover+letter+template+structure
    • http://files.purposefullearning.net/uploads/1/3/0/9/130969842/noxugugasu.pdf
    • http://roxogom.rockswcd.org/uploads/1/3/1/4/131453574/fafagul-zadevenokix-kitubodut.pdf
    • https://cdn.shopify.com/s/files/1/0430/4352/0666/files/9840689695.pdf
    • https://cdn.shopify.com/s/files/1/0434/5951/0424/files/najizedozarolimiji.pdf
    • https://cdn.shopify.com/s/files/1/0430/5797/1362/files/pafesoruv.pdf
    • https://cdn.shopify.com/s/files/1/0433/2408/0282/files/32173404126.pdf
    • https://cdn.shopify.com/s/files/1/0433/9289/3093/files/is_11513_download.pdf
    • https://cdn.shopify.com/s/files/1/0449/7971/6264/files/accounting_golden_rules_in_tamil.pdf
    • https://cdn.shopify.com/s/files/1/0433/4691/9579/files/41824505151.pdf
    • https://cdn.shopify.com/s/files/1/0438/3545/7698/files/roluruwaja.pdf
    • https://cdn.shopify.com/s/files/1/0431/6259/9584/files/99256574199.pdf
    • https://cdn.shopify.com/s/files/1/0435/5053/9940/files/define_noblesse_oblige.pdf
    • https://cdn.shopify.com/s/files/1/0440/6326/0822/files/20201621174.pdf
    • https://cdn.shopify.com/s/files/1/0433/6100/9814/files/hsslive_computer_science_answer_key.pdf
    • https://cdn.shopify.com/s/files/1/0429/2925/8649/files/advantages_and_disadvantages_of_internet_communication.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_off000081c1.bin
fb910fcaccfb69e7e24f4a01418b571d84f4a45acc3a1eb8094a70c54d81c93b
pdf-font-stream PDF embedded font (sfnt) at offset 0x81C1 5044 bytes
font_01_sfnt_off000092d1.bin
c2488749fa1527174ed4aefdc014ee4fdbdd5ea3f5bad13ff42fb03d73683a60
pdf-font-stream PDF embedded font (sfnt) at offset 0x92D1 10648 bytes