Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea8bf70fc85c5016…

MALICIOUS

PDF

42.7 KB Created: 2020-08-14 21:50:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d97cd82b3e3b14c6041bab68f6d9d129 SHA-1: b449c0801ef93dc325f29e9b468c1af5edbf24bc SHA-256: ea8bf70fc85c50168ad7204d85ee0039de2c76014e75691282061f9d46d6aabf
152 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to ttraff.ru. The document body, though obfuscated, contains the same URL and appears to be a lure for educational content. The presence of numerous other PDF links, many hosted on Shopify, suggests a link farm or SEO poisoning tactic to distribute malicious content. The ML classifier also 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=free+irony+worksheets+for+middle+school
    • http://files.holtowltrail.co.uk/uploads/1/3/0/7/130775017/gukiko.pdf
    • http://files.iconiacapital.com/uploads/1/3/1/3/131398142/begifuzan.pdf
    • http://xosuwuje.laurencoletta.org/uploads/1/3/1/4/131453028/deginazalegi.pdf
    • http://lufezev.barsbywillisphotography.com/uploads/1/3/1/4/131453323/4736712.pdf
    • http://files.asofortworth.com/uploads/1/3/1/8/131858592/1641887.pdf
    • https://cdn.shopify.com/s/files/1/0454/6340/4694/files/android_phones_that_will_support_fortnite.pdf
    • https://cdn.shopify.com/s/files/1/0430/3133/0969/files/58607442842.pdf
    • https://cdn.shopify.com/s/files/1/0428/7689/5388/files/91111702432.pdf
    • https://cdn.shopify.com/s/files/1/0429/4960/7590/files/70643342006.pdf
    • https://cdn.shopify.com/s/files/1/0436/2692/2146/files/74170252046.pdf
    • https://cdn.shopify.com/s/files/1/0431/3595/9191/files/nipumobazato.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/kexuxedixu.pdf
    • http://www.readwritethink.org/classroom-resources/lesson-plans/understanding-irony-31142.html
    • 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_off000068e8.bin
c2441204c391d985540af5621c1bb7ea83ab34478a2d649e25c079ebb04d5258
pdf-font-stream PDF embedded font (sfnt) at offset 0x68E8 5264 bytes
font_01_sfnt_off00007ac3.bin
4c00291a389187360aaa81d58204e33a5ba5b26d41f8d2affa27320119d6d55d
pdf-font-stream PDF embedded font (sfnt) at offset 0x7AC3 10192 bytes