Malicious PDF — malware analysis report

Static analysis result for SHA-256 a28d8975307ebc28…

MALICIOUS

PDF

41.5 KB Created: 2020-09-05 08:56:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1dd5ca4bb35df669a3566eb851f45310 SHA-1: 98e9aa9ac707c1bb1240d0934bbd9718f7626149 SHA-256: a28d8975307ebc280e031b6512c1438a1332cc1dc8dafec632d91707cc187a63
152 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to 'https://ttraff.me/wix?keyword=aps+university+rewa+admission+form+2018'. This URL is presented within the document body, disguised as an admission form. The presence of numerous other PDF links, many hosted on cdn.shopify.com, suggests a link farm or SEO poisoning tactic to distribute the malicious URL. 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.me/wix?keyword=aps+university+rewa+admission+form+2018
    • https://cdn.shopify.com/s/files/1/0437/4773/7754/files/medida_da_altura_uterina.pdf
    • https://cdn.shopify.com/s/files/1/0437/0399/2485/files/bhangra_gidha_song_djjohal.pdf
    • https://cdn.shopify.com/s/files/1/0463/6835/8555/files/ndaa_2020_conference_report.pdf
    • https://cdn.shopify.com/s/files/1/0463/3391/9387/files/rezawenopuvodi.pdf
    • https://cdn.shopify.com/s/files/1/0438/2906/7933/files/23148781266.pdf
    • https://static.usrfiles.com/ugd/912de2_e44b904debca4803b51928a6018e16b8.pdf
    • https://static.usrfiles.com/ugd/98e298_71f67b40a9c848e985df3107d00e85c9.pdf
    • https://static.usrfiles.com/ugd/94e5ef_022eb031ffa945948d03dd32917842f0.pdf
    • https://cdn.shopify.com/s/files/1/0439/7016/6942/files/vaxig.pdf
    • https://cdn.shopify.com/s/files/1/0435/7256/0033/files/71744938884.pdf
    • https://cdn.shopify.com/s/files/1/0428/8266/2553/files/serge_lang_algebra.pdf
    • https://cdn.shopify.com/s/files/1/0432/9363/8811/files/fininaneminodopi.pdf
    • https://cdn.shopify.com/s/files/1/0437/7785/1543/files/sijulok.pdf
    • https://cdn.shopify.com/s/files/1/0432/1958/3138/files/jisusivokut.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_off00006175.bin
492721438371a664c6ccbc16a807fedc32f41792857e03ad4e2be2cccf657fba
pdf-font-stream PDF embedded font (sfnt) at offset 0x6175 5920 bytes
font_01_sfnt_off000075aa.bin
ef8c0995a4bbb1b330cdc3c0c0f0e2396f09369eac6a1909f1f61c3d0fed5899
pdf-font-stream PDF embedded font (sfnt) at offset 0x75AA 10368 bytes