Malicious PDF — malware analysis report

Static analysis result for SHA-256 55537b56702169cf…

MALICIOUS

PDF

43.9 KB Created: 2020-08-31 16:07:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d6229e6c627020e5153b9fb790f654bc SHA-1: 41663eecd3c660d14650bfe7988753860f107e75 SHA-256: 55537b56702169cffc364567d29702d4de2b202882df7faabf366fb971d00297
152 Risk Score

Malware Insights

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

The PDF document was flagged as malicious by a machine learning classifier and contains a large number of embedded links. One of these links points to a known malicious redirector, ttraff.cc, which is likely used to obscure the final destination of the malicious payload. The document body contains garbled text but also includes the URL that triggered the malicious redirector heuristic, suggesting a lure related to 'gitlab artifacts'. The presence of a mass external PDF link farm further supports the malicious intent.

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/wix?keyword=gitlab++artifacts+from+coordinator
    • https://cdn.shopify.com/s/files/1/0428/0533/0083/files/15913363642.pdf
    • https://cdn.shopify.com/s/files/1/0435/0086/3643/files/sotenizulidozobago.pdf
    • https://cdn.shopify.com/s/files/1/0429/6146/9599/files/knife_blade_templates.pdf
    • https://cdn.shopify.com/s/files/1/0432/7325/7118/files/87608777649.pdf
    • https://static.usrfiles.com/ugd/b8c837_ef891daf819a411d8820d15b218be065.pdf
    • https://static.usrfiles.com/ugd/405339_fdc074ccaf5f4254b64d8f717d3176a0.pdf
    • https://static.usrfiles.com/ugd/23e9be_38c0f5b39a7b459a838076b9ff358d7c.pdf
    • https://cdn.shopify.com/s/files/1/0441/1867/1512/files/cambridge_english_level_placement_test.pdf
    • https://cdn.shopify.com/s/files/1/0438/1042/2941/files/bubble_chart_template_xls.pdf
    • https://static.usrfiles.com/ugd/90423f_61d5d6970464465b99bbffa658630ace.pdf
    • https://static.usrfiles.com/ugd/aef5b7_a5b4a82c8532424c846f87edd56afa24.pdf
    • https://static.usrfiles.com/ugd/cc14e4_6c117262251a46ec953416c60e083e15.pdf
    • https://static.usrfiles.com/ugd/3f80ec_91ba49563fc94bf9a535d718646eb8df.pdf
    • https://static.usrfiles.com/ugd/b8c837_e5ee22d5d4194382b5ba869f65d86ee1.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_off00006721.bin
9622ed9e0a0d51ed31220c6e594556599e719dfe4330d7da17bc99c413d5b892
pdf-font-stream PDF embedded font (sfnt) at offset 0x6721 5336 bytes
font_01_sfnt_off00007931.bin
5ac5795f5344ab8bf908d7644b6645194e0db6e51f8a74d9982733cc13d2aed7
pdf-font-stream PDF embedded font (sfnt) at offset 0x7931 12928 bytes