Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf6337442e7f2efc…

MALICIOUS

PDF

44.8 KB Created: 2020-09-03 10:25:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e9aad57929144bcc943d52834c940c90 SHA-1: 27db57f6651564ad6d948cc312c64796b9b4c1b7 SHA-256: cf6337442e7f2efccca678f5c9385b3454b869fbb7f16fa2a50b76b33ce68fc5
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a critical heuristic firing for a malicious redirector link, specifically 'https://ttraff.link/pify?keyword=multiple+checkbox+checked+in+android'. This indicates the document is designed to lure users to a potentially harmful destination. The presence of a large number of external PDF links, many hosted on static.usrfiles.com, suggests a link farm or SEO poisoning tactic to improve search engine visibility for malicious content. 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.link/pify?keyword=multiple+checkbox+checked+in+android
    • https://static.usrfiles.com/ugd/974a4e_5740ffa894294cbf8cd221094d88bf1d.pdf
    • https://static.usrfiles.com/ugd/80bfa9_3c5a2fc72f3b45d193c47713c7957120.pdf
    • https://static.usrfiles.com/ugd/c345b0_73b28149451849ab8b4e5d538e8b8920.pdf
    • https://cdn.shopify.com/s/files/1/0431/2930/7293/files/6958954930.pdf
    • https://cdn.shopify.com/s/files/1/0432/1270/1854/files/75370677089.pdf
    • https://cdn.shopify.com/s/files/1/0440/7292/7384/files/81218877259.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/15138334831.pdf
    • https://static.usrfiles.com/ugd/a771bd_fad8b45417cb43278f7b6b674f3ef2f8.pdf
    • https://static.usrfiles.com/ugd/eaf48f_ab998c950f3344f2918b14150dcbd0c2.pdf
    • https://static.usrfiles.com/ugd/eaf48f_600a586820fd4d30b8def14d8ab1583b.pdf
    • https://static.usrfiles.com/ugd/0789d5_1ef5a2af93aa4f1191f60d7dab598ad8.pdf
    • https://static.usrfiles.com/ugd/4b874d_1c284c269ba0432289ad8c0b46fa0ad1.pdf
    • https://cdn.shopify.com/s/files/1/0428/0002/1667/files/88227120704.pdf
    • https://cdn.shopify.com/s/files/1/0431/6214/0826/files/82277836114.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000067f8.bin
fba772cfc47e79958818aeb1f62fde732b0b4906b82b1c3e8996c388495051a7
pdf-font-stream PDF embedded font (sfnt) at offset 0x67F8 5260 bytes
font_01_sfnt_off000079cf.bin
87f4dc9fc1dc24012f317389c1eb0370a9430534078bbe5b7f9ba8065666d42c
pdf-font-stream PDF embedded font (sfnt) at offset 0x79CF 1956 bytes
font_02_sfnt_off000082f0.bin
bcf8405d1dfaa5895f419999d1b0feb5a0f28a54204f2df94f8303a248314ea0
pdf-font-stream PDF embedded font (sfnt) at offset 0x82F0 10240 bytes