Malicious PDF — malware analysis report

Static analysis result for SHA-256 c93ec11cdf5cedcf…

MALICIOUS

PDF

35.9 KB Created: 2020-08-29 18:23:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1e09e2ac4924b70e67c45b82a7331fe5 SHA-1: 2743710c70039084970c67e1e681215ff2075c8b SHA-256: c93ec11cdf5cedcf9584a696b3037599905473a6774f24741b07f26ee7ce0320
152 Risk Score

Malware Insights

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

The PDF was flagged by a critical heuristic for linking to known malicious redirector infrastructure. Additionally, it contains a mass of external links, identified as a PDF link farm, suggesting a tactic to distribute malicious content or engage in SEO spam. The ML classifier also strongly indicated maliciousness. No scripts were extracted, and the document body was largely unreadable binary data, but the presence of the malicious redirector URL is a high-confidence indicator.

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.com/wix?keyword=ed+eagle+series+by+stuart+woods
    • https://cdn.shopify.com/s/files/1/0431/6646/6216/files/rozabajorujotifixu.pdf
    • https://cdn.shopify.com/s/files/1/0440/7282/9078/files/jidomumabifexaw.pdf
    • https://cdn.shopify.com/s/files/1/0431/0115/9575/files/b._sc_nursing_syllabus_inc.pdf
    • https://static.usrfiles.com/ugd/7f46b5_7645efe85a3943d2983e1ef283b68077.pdf
    • https://static.usrfiles.com/ugd/7e6083_dc37fbd1cf21473d92c486ec701b485e.pdf
    • https://static.usrfiles.com/ugd/b8c837_19264833cbd04ddc9aec8a20a8d52c93.pdf
    • https://cdn.shopify.com/s/files/1/0435/6079/6318/files/jologifozevaveponowun.pdf
    • https://cdn.shopify.com/s/files/1/0430/6426/2818/files/akihabara_map.pdf
    • https://cdn.shopify.com/s/files/1/0437/0386/1401/files/grandfather_mountain_weather_report.pdf
    • https://cdn.shopify.com/s/files/1/0430/1396/3939/files/wejawuxinak.pdf
    • https://cdn.shopify.com/s/files/1/0430/8946/1410/files/48780110753.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_off00004f5e.bin
755b4e4b982753ab3d69eedb67db3538c14dbdde14d4fd60a625b743223bb8c9
pdf-font-stream PDF embedded font (sfnt) at offset 0x4F5E 5284 bytes
font_01_sfnt_off00006172.bin
4e64a2ac2ec38d41fb49abc0e5a7837fe83f769583251029f03d94333b7c4baf
pdf-font-stream PDF embedded font (sfnt) at offset 0x6172 9800 bytes