Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bfdf6af92cc1cf9…

MALICIOUS

PDF

44.5 KB Created: 2020-08-21 09:28:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cafd2cbd229e37cf5140ea2266a4bdc6 SHA-1: f7e3e0137a3c419b9cda2ba579c811f670d66abd SHA-256: 4bfdf6af92cc1cf9eb529b81dfa4b4ede2340a7061171ef1c4af5e34cc9f290e
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, which is further supported by the presence of a PDF link farm. The document body, though heavily obfuscated, contains text related to a 'medical assistant certification study guide pdf' and a URL that appears to be a redirector. The primary malicious activity observed is the redirection of users to potentially harmful content via the ttraff.cc domain.

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=medical+assistant+certification+study+guide+pdf
    • http://ledunivit.beckyyates.com/uploads/1/3/2/7/132740185/tijivemutufu-suxelisewefalu.pdf
    • http://files.blackdogfabrication.com/uploads/1/3/1/3/131383727/9228740.pdf
    • http://vexir.bauermeistertree.com/uploads/1/3/1/6/131607305/3d4182c819.pdf
    • http://files.more-cb.com/uploads/1/3/1/4/131437484/galogi-fozubisomu-bolisuxumer-libasikibeva.pdf
    • https://cdn.shopify.com/s/files/1/0431/7839/3749/files/gstr_9a_annual_return.pdf
    • https://cdn.shopify.com/s/files/1/0429/8519/3621/files/10299855546.pdf
    • https://cdn.shopify.com/s/files/1/0432/6073/9752/files/unblock_phone_numbers_on_android.pdf
    • https://cdn.shopify.com/s/files/1/0461/8587/3561/files/94937365440.pdf
    • https://cdn.shopify.com/s/files/1/0428/8161/3987/files/58682572800.pdf
    • https://cdn.shopify.com/s/files/1/0430/8769/1925/files/14751091128.pdf
    • https://cdn.shopify.com/s/files/1/0434/3506/5505/files/83463868552.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000619a.bin
60f1a4180ae63468c36852450d9e6cd59965ed8f8d47fac14f225fe75ae9b165
pdf-font-stream PDF embedded font (sfnt) at offset 0x619A 5312 bytes
font_01_sfnt_off000073ba.bin
4753c33dfbd4411c2e36eec640970a46db2afb9e7aae6380ae1958d977779e2e
pdf-font-stream PDF embedded font (sfnt) at offset 0x73BA 10396 bytes
font_02_sfnt_off00009723.bin
b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c
pdf-font-stream PDF embedded font (sfnt) at offset 0x9723 4324 bytes