Malicious PDF — malware analysis report

Static analysis result for SHA-256 b89a72c72ecc1241…

MALICIOUS

PDF

43.7 KB Created: 2020-08-05 11:54:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 25c1b7746f624fd2a65739bdaca9f722 SHA-1: 8509ed5194d5caf98c3a1eee89a54a6105d9ae14 SHA-256: b89a72c72ecc1241770b966a86adfef33bf9676a27ea08da8c281c8db5223e6e
154 Risk Score

Malware Insights

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

The PDF contains a link farm designed to appear as a free download for a technical book, but the primary link redirects to a known malicious infrastructure. The ML classifier strongly indicated maliciousness, and the PDF structure suggests a link-based lure. The embedded URLs are part of a link farm strategy to obscure the malicious redirector.

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=data+structures+and+algorithms+made+easy+karumanchi+pdf
    • http://files.pilipinaskalikasan.com/uploads/1/3/1/6/131636990/komovole.pdf
    • http://files.nichellerenee.solutions/uploads/1/3/1/4/131406527/guratasagejako.pdf
    • http://files.waiwichita.org/uploads/1/3/0/9/130969474/nujimegegebose.pdf
    • https://cdn.shopify.com/s/files/1/0434/4568/2328/files/kufogufol.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/rabilividobakomitunaxizug.pdf
    • https://cdn.shopify.com/s/files/1/0432/5395/6758/files/pofaforemex.pdf
    • https://cdn.shopify.com/s/files/1/0431/0587/8170/files/zomig.pdf
    • https://cdn.shopify.com/s/files/1/0427/4687/1974/files/43865826643.pdf
    • https://cdn.shopify.com/s/files/1/0431/0643/5232/files/64867924223.pdf
    • https://cdn.shopify.com/s/files/1/0428/9980/0217/files/dicionario_aramaico_portugues.pdf
    • https://cdn.shopify.com/s/files/1/0438/2490/6397/files/79709531382.pdf
    • https://cdn.shopify.com/s/files/1/0431/8602/8708/files/terminal_command_line_cheat_sheet.pdf
    • https://cdn.shopify.com/s/files/1/0441/3338/4344/files/mb_publication_english_book_for_bank_clerk.pdf
    • https://cdn.shopify.com/s/files/1/0431/5329/3469/files/active_listening_psychology.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_off00005cc4.bin
b948ac3724e6c7ff6e885952275fb84161a4c6b6196ba6a58f723dff584ac516
pdf-font-stream PDF embedded font (sfnt) at offset 0x5CC4 5616 bytes
font_01_sfnt_off00006fba.bin
406ace54f221e3331569fdf4fb17054c8c405e241bf7715897faa50bb96faf8d
pdf-font-stream PDF embedded font (sfnt) at offset 0x6FBA 10520 bytes
font_02_sfnt_off0000938b.bin
9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x938B 4324 bytes