Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f311cf9b23b589c…

MALICIOUS

PDF

55.3 KB Created: 2020-07-30 20:07:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f1b1f16ec3add90ddec40cbc27217358 SHA-1: ebeeb1e3e4119982fb52d5f37e153858e552db94 SHA-256: 8f311cf9b23b589cf159434a9c0fc58f27aa26995cd910e1d247f4dec59aea55
152 Risk Score

Malware Insights

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

The PDF contains multiple embedded URLs, with one identified as a known malicious redirector (ttraff.cc). The ML classifier strongly flagged this PDF as malicious. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and a date, suggesting it was generated programmatically. The primary attack pattern involves luring the user to click on the malicious redirector 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.cc/pify?keyword=capitu+e+bentinho+pdf
    • http://files.asyouwishsxm.com/uploads/1/3/2/6/132683000/e2033.pdf
    • http://files.cookscreekchurch.org/uploads/1/3/2/7/132712214/kaxutuli.pdf
    • http://files.jewelerinthewoods.com/uploads/1/3/2/8/132814071/rorunik.pdf
    • http://files.bigsandlakepoa.org/uploads/1/3/0/8/130873804/digekox-pevujed-pufelolej.pdf
    • http://files.fitzpatrickecologicalconsulting.com/uploads/1/3/1/1/131163635/09ac9c.pdf
    • https://cdn.shopify.com/s/files/1/0432/1447/1330/files/bakupagumo.pdf
    • https://cdn.shopify.com/s/files/1/0431/1790/4033/files/19630438775.pdf
    • https://cdn.shopify.com/s/files/1/0440/5392/1957/files/17991363793.pdf
    • https://cdn.shopify.com/s/files/1/0432/6182/1083/files/majajikirokotesolesu.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/44994208471.pdf
    • https://cdn.shopify.com/s/files/1/0434/0360/8216/files/wazevig.pdf
    • https://cdn.shopify.com/s/files/1/0439/9307/1774/files/desofemuximexutowabajox.pdf
    • https://cdn.shopify.com/s/files/1/0429/5114/7676/files/ramefakawidomobopepede.pdf
    • https://cdn.shopify.com/s/files/1/0436/6349/1222/files/pesovujemeg.pdf
    • https://cdn.shopify.com/s/files/1/0430/9378/6791/files/98156868720.pdf
    • https://cdn.shopify.com/s/files/1/0432/4953/3088/files/36847479167.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_off000096d0.bin
993ba8957fd49bc47924822176a73ce4ed405fbab164dc3c4482d0d57aeccf8c
pdf-font-stream PDF embedded font (sfnt) at offset 0x96D0 4868 bytes
font_01_sfnt_off0000a751.bin
b8ebd256508fb4f669beb40fc863ec6d9697c50e954b7e11b1691f9a39eb85f4
pdf-font-stream PDF embedded font (sfnt) at offset 0xA751 12868 bytes