Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f7f733266088c12…

MALICIOUS

PDF

67.0 KB Created: 2020-08-31 20:32:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d79140818d45d5e776c25d2cbc4a2fbf SHA-1: 7c2ea08fc43969cba3c90a028322faba60064b21 SHA-256: 8f7f733266088c12ba466ff4bbe28b3002fb546bca1893472b79bba126b7e9c4
152 Risk Score

Malware Insights

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

The PDF file contains a critical heuristic firing for a malicious redirector link, pointing to 'https://ttraff.ru/wix?keyword=internship+acknowledgement+template'. This URL is presented within the document body, disguised as an internship acknowledgement template. The file also triggered a critical heuristic for a PDF SEO link farm, indicating a large number of outbound links, many of which are generated and potentially malicious. The ML classifier also strongly flagged this PDF as malicious.

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/wix?keyword=internship+acknowledgement+template
    • https://static.usrfiles.com/ugd/30e015_4d259bb5c4644d5fa5ba0ab54626489c.pdf
    • https://static.usrfiles.com/ugd/b8c837_cf7e75be42e84fb39461b4b2bf6d0847.pdf
    • https://static.usrfiles.com/ugd/33a2e4_2909d49279fa4675ae7048b209a1f8ad.pdf
    • https://static.usrfiles.com/ugd/1b8612_097cf579b8674f63af9960402a16e644.pdf
    • https://static.usrfiles.com/ugd/d01287_2b2aa72c0cda469ba0cd76d4c8894229.pdf
    • https://cdn.shopify.com/s/files/1/0429/3731/9590/files/tabanokuxati.pdf
    • https://cdn.shopify.com/s/files/1/0432/5041/7827/files/tilenabulinu.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/talijofazejodo.pdf
    • https://cdn.shopify.com/s/files/1/0432/2364/6365/files/barcelona_kit_15_16.pdf
    • https://static.usrfiles.com/ugd/b8c837_cb6f0d2e3f224ffdbc54b9370b056c71.pdf
    • https://static.usrfiles.com/ugd/60933b_1f1e0b93619a422db3b5f891488b42b6.pdf
    • https://cdn.shopify.com/s/files/1/0429/1998/5319/files/nalaxi.pdf
    • https://cdn.shopify.com/s/files/1/0427/7708/4070/files/88161826740.pdf
    • https://cdn.shopify.com/s/files/1/0430/9401/6157/files/82648610955.pdf
    • https://cdn.shopify.com/s/files/1/0430/5331/8298/files/pdf_to_word_converter_not_editable.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_off0000c9c5.bin
94581a2c4e88b8f65f5bc446cf3d86cbb39105f5306d6e37964db65b99e631fb
pdf-font-stream PDF embedded font (sfnt) at offset 0xC9C5 5580 bytes
font_01_sfnt_off0000dca7.bin
ae52f2f76342eb9e6a9ca36300552f39705e24153289bab48f1e4c02cc32a6ad
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCA7 10040 bytes