Malicious PDF — malware analysis report

Static analysis result for SHA-256 f908daf76c141823…

MALICIOUS

PDF

41.3 KB Created: 2020-08-14 21:24:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2ca1865136cdaef84f618646f2b2c73d SHA-1: 37f5eccf22c96354245ba1df09a78dea9892f04d SHA-256: f908daf76c14182318625926a2652d2d7ee49b81166900dd6c7a951f9d07f6ea
154 Risk Score

Malware Insights

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

The PDF contains a mass external link farm, with a primary link directing to a known malicious redirector. The document body, though heavily obfuscated, contains the URL that leads to the redirector, suggesting a lure to a malicious site. The ML classifier strongly supports the malicious nature of this PDF.

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=latitude+and+longitude+worksheets+4th+grade+pdf
    • http://pibofeda.bbbchimacum.com/uploads/1/3/1/3/131384401/bopajasivuzoz-pazaniredezik.pdf
    • http://files.themistyvalley.com/uploads/1/3/1/4/131406885/7057437.pdf
    • http://files.thebsp.org/uploads/1/3/2/6/132680905/merijasam-wezuwid-wuxubawepugovox.pdf
    • https://cdn.shopify.com/s/files/1/0433/7470/6853/files/puvobefimomutonegulofo.pdf
    • https://cdn.shopify.com/s/files/1/0432/8361/1801/files/zejumiwawilelejuva.pdf
    • https://cdn.shopify.com/s/files/1/0433/0097/8853/files/pugeda.pdf
    • https://cdn.shopify.com/s/files/1/0428/3708/2271/files/ledezoju.pdf
    • https://cdn.shopify.com/s/files/1/0431/6259/9586/files/tekewuvixizobifazesimal.pdf
    • https://cdn.shopify.com/s/files/1/0431/0119/2352/files/bertrand_russell_human_knowledge_its_scope_and_limits.pdf
    • https://cdn.shopify.com/s/files/1/0429/0910/6343/files/37247919223.pdf
    • https://cdn.shopify.com/s/files/1/0439/3605/5454/files/lemony_snicket.pdf
    • https://cdn.shopify.com/s/files/1/0430/0944/1953/files/pujigomadinomisumuronimo.pdf
    • https://cdn.shopify.com/s/files/1/0433/3423/8362/files/23328180661.pdf
    • https://cdn.shopify.com/s/files/1/0431/2426/1026/files/thyroid_gland_function.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_off00006401.bin
97af129344d46aac8acc71d6732def534ab36152401aaa71cf7f846e32b05043
pdf-font-stream PDF embedded font (sfnt) at offset 0x6401 5488 bytes
font_01_sfnt_off000076bf.bin
227636b3c9193ac46d9eac87be00895d56e0fe4c55e4df2fe3dd2f1f6828f0e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x76BF 9888 bytes