Malicious PDF — malware analysis report

Static analysis result for SHA-256 8421b50b767ee0cb…

MALICIOUS

PDF

46.6 KB Created: 2020-08-04 04:25:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c4ade6c382314add94728ce1badf7c71 SHA-1: 528db88f9f1eb21a6ddb8995b4ff3ce1403160b7 SHA-256: 8421b50b767ee0cb72e6756ce14f5e7c305e75715ab7ca1430aab2293d1ae505
152 Risk Score

Malware Insights

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

The PDF contains embedded links that point to a known malicious redirector, which is designed to lead users to malicious content. The document body, though corrupted, suggests a lure related to 'carpal tunnel syndrome patient information'. The presence of a link farm heuristic further indicates an attempt to distribute malicious content through SEO-like tactics. The ML classifier strongly flagged this PDF as malicious.

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=carpal+tunnel+syndrome+patient+information+pdf
    • http://files.moto-camino.com/uploads/1/3/1/4/131483772/numed_nisofoxiwem_rejisatazob.pdf
    • http://files.cancanliners.com/uploads/1/3/0/7/130775228/212d5aafaf7370.pdf
    • http://files.sedonaweddingessentials.com/uploads/1/3/0/8/130814124/5461353.pdf
    • http://files.sergey-gusev.com/uploads/1/3/1/8/131871740/8276357.pdf
    • https://cdn.shopify.com/s/files/1/0439/6217/1550/files/46670818651.pdf
    • https://cdn.shopify.com/s/files/1/0434/3257/5132/files/tuwilaxamigofedotixeduv.pdf
    • https://cdn.shopify.com/s/files/1/0435/0086/3643/files/intercessory_prayer_manual.pdf
    • https://cdn.shopify.com/s/files/1/0430/9313/1425/files/78510508902.pdf
    • https://cdn.shopify.com/s/files/1/0433/5943/6951/files/67259557608.pdf
    • https://cdn.shopify.com/s/files/1/0430/4466/7553/files/judusir.pdf
    • https://cdn.shopify.com/s/files/1/0428/8158/1209/files/lejim.pdf
    • https://cdn.shopify.com/s/files/1/0433/4141/4555/files/39250483081.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/27247465441.pdf
    • https://cdn.shopify.com/s/files/1/0430/4414/3253/files/road_conditions_i_5_siskiyou_pass.pdf
    • https://cdn.shopify.com/s/files/1/0432/9157/4430/files/41208086243.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_off000078cd.bin
292af1d0ae8577ef802c65880c482af010026c000bec535ccc6e5840aeb408bd
pdf-font-stream PDF embedded font (sfnt) at offset 0x78CD 5196 bytes
font_01_sfnt_off00008a63.bin
42be385fb2707449f2637d3d51020906587fa753e01359654ba799c0782ed724
pdf-font-stream PDF embedded font (sfnt) at offset 0x8A63 10088 bytes