Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbef544c33e17834…

MALICIOUS

PDF

57.4 KB Created: 2020-08-05 22:45:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e74d0e0c8a7d1aa27b03092de86152c8 SHA-1: c8fc70c7b0663d99c7369fb3af9c0a6777cc9574 SHA-256: fbef544c33e178346ada1c1fb4f420e8d7c7ef9772d036fa121d3f8d75ec5eb4
154 Risk Score

Malware Insights

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

The PDF contains a link that redirects to a malicious URL, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body, though heavily obfuscated, contains the string 'https://ttraff.cc/pify?keyword=biophysics+course+pdf', suggesting a lure for a 'biophysics course pdf'. The PDF_SEO_LINK_FARM heuristic indicates a large number of external links, likely for SEO manipulation or to host further malicious content. The ML classifier 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.cc/pify?keyword=biophysics+course+pdf
    • http://files.theoldiesshowny.com/uploads/1/3/0/7/130739348/414c5.pdf
    • http://files.azgpc.org/uploads/1/3/1/6/131637240/f69b4c6929.pdf
    • http://files.junctioncraft.com/uploads/1/3/1/8/131871687/norasifutisiwaridipa.pdf
    • http://files.goodgirlsgonegrimm.com/uploads/1/3/0/7/130776749/9022892.pdf
    • https://cdn.shopify.com/s/files/1/0430/6301/7629/files/57585686909.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/miveguxuxububepevomozit.pdf
    • https://cdn.shopify.com/s/files/1/0429/7677/2250/files/lazivakamexupudogoje.pdf
    • https://cdn.shopify.com/s/files/1/0429/6825/2565/files/xumitiwamoxiribusowoke.pdf
    • https://cdn.shopify.com/s/files/1/0428/8797/0975/files/tovinibavesizodoves.pdf
    • https://cdn.shopify.com/s/files/1/0431/7016/8986/files/mefasirigi.pdf
    • https://cdn.shopify.com/s/files/1/0430/0229/8521/files/ziwoxepigofazapaguj.pdf
    • https://cdn.shopify.com/s/files/1/0429/9295/9642/files/39118528471.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/23929268289.pdf
    • https://cdn.shopify.com/s/files/1/0428/5402/3327/files/gedavorunakituvurejigulej.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/nimapudusakodinufuzexive.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_off0000a213.bin
f789a03aa0f58c2a01c2a2156be22d9943dd1e70bb747a33ae1a03465fcb9183
pdf-font-stream PDF embedded font (sfnt) at offset 0xA213 5152 bytes
font_01_sfnt_off0000b3a2.bin
72c24f330ae515621425fb0436308b1418cc96536779578ee197ed1ad1b7a662
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3A2 11208 bytes