Malicious PDF — malware analysis report

Static analysis result for SHA-256 26bf0febe8f541cf…

MALICIOUS

PDF

49.5 KB Created: 2020-08-09 17:49:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c5f03d920dfb68be796db0a8a3937dbf SHA-1: f3bd84462a6078038509aa4dcc125b2bac7bcfa4 SHA-256: 26bf0febe8f541cf7d95c555399599d0cc2c904f884ba0f4232f04b8086283b2
152 Risk Score

Malware Insights

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

The PDF file contains numerous embedded links, many of which point to a link farm hosted on Shopify. One critical heuristic identified a link to a known malicious redirector, ttraff.cc, which is likely used to obscure the final malicious destination. The ML classifier strongly indicates maliciousness. The document body, though heavily obfuscated, contains the URL https://ttraff.cc/pify?keyword=walden+thoreau+pdf+italiano, suggesting a lure to a malicious site.

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=walden+thoreau+pdf+italiano
    • http://files.legacysportsusa.com/uploads/1/3/1/4/131438538/pafijepulobo_rutigolaril.pdf
    • http://files.cotyandmadison.com/uploads/1/3/1/1/131164506/2186121.pdf
    • http://files.drwasniewski.com/uploads/1/3/1/0/131071114/raxovulofa.pdf
    • http://files.farbeyondthemiyako.com/uploads/1/3/0/7/130776268/rovudedegijo.pdf
    • https://cdn.shopify.com/s/files/1/0451/6475/7146/files/50423099600.pdf
    • https://cdn.shopify.com/s/files/1/0430/9018/2304/files/sisodafidititap.pdf
    • https://cdn.shopify.com/s/files/1/0428/9229/6358/files/85642322425.pdf
    • https://cdn.shopify.com/s/files/1/0428/7306/1532/files/26650254612.pdf
    • https://cdn.shopify.com/s/files/1/0440/8626/3960/files/2020_aha_guidelines_for_cpr_and_ecc.pdf
    • https://cdn.shopify.com/s/files/1/0436/6221/3273/files/chauvet_colorstrip_manual.pdf
    • https://cdn.shopify.com/s/files/1/0431/1485/6610/files/atal_pension_yojana_tamil.pdf
    • https://cdn.shopify.com/s/files/1/0431/0587/8170/files/struktury_leksykalno_gramatyczne_angielski_matura.pdf
    • https://cdn.shopify.com/s/files/1/0434/6321/3209/files/58598129512.pdf
    • https://cdn.shopify.com/s/files/1/0433/3826/8830/files/xigidedukafoxodigepi.pdf
    • https://cdn.shopify.com/s/files/1/0433/9829/9813/files/73863807065.pdf
    • https://cdn.shopify.com/s/files/1/0431/5955/2155/files/68713042454.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_off000085e9.bin
c909698dfd56b2038c7469d4b7cb28e065c7c99584c4055e2f769d576f1757c5
pdf-font-stream PDF embedded font (sfnt) at offset 0x85E9 4964 bytes
font_01_sfnt_off000096d2.bin
e43228c1591569521771d6657a0b74f09043b30854dc522d6fa1f15424769b81
pdf-font-stream PDF embedded font (sfnt) at offset 0x96D2 9980 bytes