Malicious PDF — malware analysis report

Static analysis result for SHA-256 20cb0be1675ea27a…

MALICIOUS

PDF

43.4 KB Created: 2020-08-30 20:41:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2340d8f2eec9d28f45286d6d3cede28b SHA-1: afec37b9b44ede246caa91abd9da40e8f58fa660 SHA-256: 20cb0be1675ea27a9ba24d3678f3836fb7543aa89ef3412864554aa3c285adea
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to Shopify domains hosting other PDFs, but one critical link directs to a known malicious redirector. The document body, though heavily obfuscated, contains text that appears to be a lure related to 'Assassin's Creed Black Flag'. The ML classifier strongly flagged this PDF as malicious, indicating a high likelihood of 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=assassin%2527s+creed+black+flag+missio
    • https://cdn.shopify.com/s/files/1/0432/5205/6227/files/givewupajefuta.pdf
    • https://cdn.shopify.com/s/files/1/0430/0524/7647/files/piseselu.pdf
    • https://cdn.shopify.com/s/files/1/0428/6355/8815/files/alimentos_organicos_definicion.pdf
    • https://static.usrfiles.com/ugd/fd3290_7c9a38406b4044cfbcb9f6c63ac5e820.pdf
    • https://static.usrfiles.com/ugd/b8c837_eeb7b8ec05764115b8b8a780d8230f3b.pdf
    • https://static.usrfiles.com/ugd/b8c837_e4c74ce23ce048c8a561d8482d1d311c.pdf
    • https://static.usrfiles.com/ugd/b8c837_ce64934b18b9454eb1cd4b0ec1c38508.pdf
    • https://cdn.shopify.com/s/files/1/0465/4917/2382/files/77027572698.pdf
    • https://cdn.shopify.com/s/files/1/0431/3019/2039/files/mean_value_theorem_for_derivatives.pdf
    • https://cdn.shopify.com/s/files/1/0432/9819/3573/files/early_pregnancy_essay.pdf
    • https://cdn.shopify.com/s/files/1/0430/3116/7137/files/repopomabarepoxasivol.pdf
    • https://cdn.shopify.com/s/files/1/0430/6498/3703/files/kozagitefu.pdf
    • https://cdn.shopify.com/s/files/1/0428/9898/1030/files/applied_economics_module_for_grade_11.pdf
    • https://cdn.shopify.com/s/files/1/0462/1287/4394/files/flowers_for_algernon_activities.pdf
    • https://cdn.shopify.com/s/files/1/0429/5553/8595/files/anatomy_for_sculptors_uldis_zarins.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_off000068c4.bin
85186148e069c9d8d94a2ef4ece632188b38d304e918b090a71d1bcb914077d8
pdf-font-stream PDF embedded font (sfnt) at offset 0x68C4 5568 bytes
font_01_sfnt_off00007b9d.bin
e68c3a87d8514b031198d4ce572958fc3981f2d0e05081eff1c692e0e2f61081
pdf-font-stream PDF embedded font (sfnt) at offset 0x7B9D 11260 bytes