Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8cac2155a38903e…

MALICIOUS

PDF

42.1 KB Created: 2020-08-21 23:47:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 35abc04561ebb808fa69f8893c7b9438 SHA-1: 02ca27e7c76643fe4b707cffb09fb01aa592459e SHA-256: e8cac2155a38903e4669bd69b77623330d0aa39937788d9e96a65607a7caefe2
152 Risk Score

Malware Insights

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

The PDF was flagged as malicious by a machine learning classifier and contains numerous embedded links. One critical heuristic identified a link to a known malicious redirector, ttraff.cc, which likely serves to obscure the ultimate destination of the attack. Another critical heuristic noted a large number of external PDF links, suggesting a link farm or SEO poisoning attempt. The document body contains garbled text but includes the same redirector URL and several Shopify-hosted PDF links.

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=happy+birthday+to+you+flute+sheet+music
    • http://files.thosefunnylittlepeople.com/uploads/1/3/1/4/131453156/6ecc0.pdf
    • http://files.housenbuildings.com/uploads/1/3/1/1/131164199/gexorodudo-gerufatew.pdf
    • http://files.levelupwithaleana.com/uploads/1/3/0/8/130813427/7196367.pdf
    • https://cdn.shopify.com/s/files/1/0440/2606/9157/files/24317495143.pdf
    • https://cdn.shopify.com/s/files/1/0431/7636/2150/files/cdc_flu_shot_2018_information_sheet.pdf
    • https://cdn.shopify.com/s/files/1/0440/0254/1726/files/22448200797.pdf
    • https://cdn.shopify.com/s/files/1/0436/5654/4409/files/anemia_defisiensi_besi_idai.pdf
    • https://cdn.shopify.com/s/files/1/0436/8039/9513/files/79598855044.pdf
    • https://cdn.shopify.com/s/files/1/0433/2906/1032/files/55428448972.pdf
    • https://cdn.shopify.com/s/files/1/0429/1274/3591/files/juwenu.pdf
    • https://cdn.shopify.com/s/files/1/0434/2199/1079/files/49705211079.pdf
    • https://cdn.shopify.com/s/files/1/0435/6059/9701/files/sozis.pdf
    • https://cdn.shopify.com/s/files/1/0434/1704/3111/files/jefizikive.pdf
    • https://cdn.shopify.com/s/files/1/0428/3075/8054/files/88180118107.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_off00006555.bin
9801d4865033463b72c6b5f0cd11abd37de8490b0b6f876bddb2adf12d009d90
pdf-font-stream PDF embedded font (sfnt) at offset 0x6555 5600 bytes
font_01_sfnt_off00007836.bin
33c506cb04e658baedcdc002dd6797aa7fe70600b0e4739f4a5ea4af1490a754
pdf-font-stream PDF embedded font (sfnt) at offset 0x7836 10272 bytes