Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4206aea81d085d8…

MALICIOUS

PDF

43.8 KB Created: 2020-07-28 22:01:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cb19d572b506ad28ed6398489211a895 SHA-1: fd90cbfd9908d478544b935885c2a916ada6940a SHA-256: b4206aea81d085d8ba3b357e952f32f7eb401cb83849a90542cfa7a7acf39f3e
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 'ttraff.ru'. Additionally, it exhibits characteristics of a PDF link farm, with numerous external links, many hosted on Shopify. The ML classifier also strongly flagged this PDF as malicious. The document body, though heavily obfuscated, contains text related to 'dried blood stains on sheets', likely a lure to entice clicks on the embedded malicious 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=dried+blood+stains+on+sheets
    • http://files.gillianjoy.com/uploads/1/3/0/8/130813982/mizuzunijawun_xatopaviperi_rigakegaf.pdf
    • http://files.melisakaye.com/uploads/1/3/1/3/131379873/nudiz-milawiru.pdf
    • http://files.addictionsss.com/uploads/1/3/1/4/131406785/dozejenomodut_mifebemuwovegi.pdf
    • http://files.mrstuckeysclass.com/uploads/1/3/0/7/130776841/4143467.pdf
    • http://files.gillia
    • https://cdn.shopify.com/s/files/1/0429/9436/8663/files/jefofiritema.pdf
    • https://cdn.shopify.com/s/files/1/0433/0009/4112/files/78901900570.pdf
    • https://cdn.shopify.com/s/files/1/0435/7285/4939/files/37521608871.pdf
    • https://cdn.shopify.com/s/files/1/0435/0532/0088/files/zosaribafekatobisizejimo.pdf
    • https://cdn.shopify.com/s/files/1/0431/1715/0368/files/xasidavorinabekisup.pdf
    • https://cdn.shopify.com/s/files/1/0430/9227/9460/files/jekeluga.pdf
    • https://cdn.shopify.com/s/files/1/0438/2100/7005/files/87914397536.pdf
    • https://cdn.shopify.com/s/files/1/0438/1540/3682/files/lijekenifopupadu.pdf
    • https://cdn.shopify.com/s/files/1/0430/0944/1953/files/sitadajasidopuxidekad.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/sezam.pdf
    • https://cdn.shopify.com/s/files/1/0434/0708/1622/files/62713583126.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_off00006f99.bin
e65604b571b1eca9e17f6a64e2fabe46a4295f2e100644c19bde80eaa036137d
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F99 4840 bytes
font_01_sfnt_off00007fef.bin
25a070b3489ca983a87a27588822c66b409196be35b280a936e75c2e0fdcf6b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x7FEF 10020 bytes