Malicious PDF — malware analysis report

Static analysis result for SHA-256 e73665f3389d7884…

MALICIOUS

PDF

40.9 KB Created: 2020-08-23 22:43:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1cb9958c5e58e392c7b75b9df5a891b3 SHA-1: 888b5fd822185e882e5e32bfddf288777435ddcb SHA-256: e73665f3389d7884ff7a3449449ea060cf578bd4a7b53338a0db36c840aab585
152 Risk Score

Malware Insights

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

The PDF was flagged as malicious by a machine learning classifier and contains a critical heuristic indicating it links to known malicious redirector infrastructure. It also contains a PDF link farm with 28 external links, many of which are hosted on cdn.shopify.com. The primary malicious URL identified is https://ttraff.ru/pify?keyword=brandt+daroff+exercise+sheet, which is likely used to redirect users to further malicious content.

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/pify?keyword=brandt+daroff+exercise+sheet
    • http://files.28thmpretired.com/uploads/1/3/1/6/131606411/totatukotim.pdf
    • http://tovutuzu.northernsoulcostablanca.com/uploads/1/3/1/4/131437778/8837818.pdf
    • http://gudox.jeromesbistro.com/uploads/1/3/1/0/131070161/3041263.pdf
    • https://cdn.shopify.com/s/files/1/0437/6847/9893/files/88590467557.pdf
    • https://cdn.shopify.com/s/files/1/0428/7240/6179/files/hambriento_nach.pdf
    • https://cdn.shopify.com/s/files/1/0432/5841/3216/files/bhai_bhai_full_movie_1997_hd.pdf
    • https://cdn.shopify.com/s/files/1/0427/5778/3718/files/juves.pdf
    • https://cdn.shopify.com/s/files/1/0429/3319/0823/files/lotugop.pdf
    • https://cdn.shopify.com/s/files/1/0430/9345/9093/files/90050004950.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/87899810879.pdf
    • https://cdn.shopify.com/s/files/1/0435/2416/1695/files/jezuvire.pdf
    • https://cdn.shopify.com/s/files/1/0456/8252/4319/files/superman_images_hd_wallpaper.pdf
    • https://cdn.shopify.com/s/files/1/0431/5339/1782/files/xapuwi.pdf
    • https://cdn.shopify.com/s/files/1/0435/4398/6330/files/82348896628.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_off0000633c.bin
c9884a7d9a00f184739970eef09e28fad288cf98160d30f3a20639b7be9fa334
pdf-font-stream PDF embedded font (sfnt) at offset 0x633C 5196 bytes
font_01_sfnt_off000074df.bin
76769af06c7597e468eb3f9058dba361340c3d479c3f504903870bf65a0e68af
pdf-font-stream PDF embedded font (sfnt) at offset 0x74DF 10024 bytes