Malicious PDF — malware analysis report

Static analysis result for SHA-256 8323379fda5277d5…

MALICIOUS

PDF

41.8 KB Created: 2020-08-20 12:23:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: de1fba8ca58931f94410c7e9c87aeafe SHA-1: 0c5340521b2178f102601bd086995e816a2fd8a0 SHA-256: 8323379fda5277d57daed94d51be22dc171cbac31bec6fcb0c44185a78f21825
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains a link that redirects to malicious infrastructure, disguised as an 'Overleaf template article'. This is further supported by heuristics indicating a malicious redirector link and a PDF link farm. The ML classifier also strongly flagged this PDF as malicious. The primary intent appears to be directing users to a malicious site via a deceptive link.

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=overleaf+template+article
    • http://files.baguanyc.com/uploads/1/3/1/4/131406104/3411093.pdf
    • http://files.buildingbridgeswma.com/uploads/1/3/1/0/131071056/85a76c3dc.pdf
    • http://rapasuke.sarahbardeen.com/uploads/1/3/2/6/132682878/vejunujirof-gunosazuw-bugikojeviv-fasanogalu.pdf
    • http://befej.nisha-alberti.com/uploads/1/3/2/3/132302872/b36306a64054.pdf
    • http://files.exploremathindemand.com/uploads/1/3/1/3/131380094/xagakukegenesara.pdf
    • https://cdn.shopify.com/s/files/1/0434/7995/7669/files/pumobavo.pdf
    • https://cdn.shopify.com/s/files/1/0436/9901/1738/files/autocad_3d_shortcut_commands.pdf
    • https://cdn.shopify.com/s/files/1/0439/5103/0430/files/pilinafewiwijafasogotim.pdf
    • https://cdn.shopify.com/s/files/1/0437/6412/1752/files/tuxazido.pdf
    • https://cdn.shopify.com/s/files/1/0430/0341/2633/files/biblia_cristiana_para_nios.pdf
    • https://cdn.shopify.com/s/files/1/0430/1458/6521/files/ganunejagejowebitu.pdf
    • https://cdn.shopify.com/s/files/1/0432/6978/3720/files/fokegupamovimudesonep.pdf
    • https://cdn.shopify.com/s/files/1/0428/5107/4204/files/52863235905.pdf
    • https://cdn.shopify.com/s/files/1/0432/2924/9694/files/73075440762.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_off00006689.bin
10557d92ae533018d7b624670fd0fec6d199c25a6e2fa93d8dc1869b455a9b46
pdf-font-stream PDF embedded font (sfnt) at offset 0x6689 5072 bytes
font_01_sfnt_off000077bb.bin
894331f935b3ccbcc0a4c3e95b957ec05910366f306275aea8368b6dae4851d4
pdf-font-stream PDF embedded font (sfnt) at offset 0x77BB 10192 bytes