Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac2fbe838bd37b4b…

MALICIOUS

PDF

37.3 KB Created: 2020-07-22 08:24:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fa979f93d2213b772e65f47c6ff7dd56 SHA-1: 01c55767ec7627a5539108d73f39fa5b47925e18 SHA-256: ac2fbe838bd37b4b777edf96b6d171db0adb8cdb0ea11ca83567140c55019bc2
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.cc'. This URL is presented within the document body, disguised as a link to 'Question tag practice worksheets with answers'. The ML classifier also strongly flagged this PDF as malicious. The primary attack vector appears to be social engineering through a deceptive link.

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/wb?keyword=question%20tag%20practice%20worksheets%20with%20answers
    • http://files.lawrencemcneil.com/uploads/1/3/2/3/132302894/2708437.pdf
    • http://files.kimfirmston.com/uploads/1/3/1/4/131452950/dulafud.pdf
    • http://files.chinherr.com/uploads/1/3/1/3/131380471/d9dda3f.pdf
    • http://files.chinherr.com/uploads/
    • https://cdn.shopify.com/s/files/1/0427/8249/0791/files/wuxepikijatilajitumovoxu.pdf
    • https://cdn.shopify.com/s/files/1/0432/7034/0772/files/dusojemobuligekes.pdf
    • https://cdn.shopify.com/s/files/1/0434/3591/7464/files/73380169867.pdf
    • https://cdn.shopify.com/s/files/1/0429/1434/9219/files/zejunarofawi.pdf
    • https://rurilaxun.files.wordpress.com/2020/06/dokefawadif.pdf
    • https://fafigunik.files.wordpress.com/2020/07/29611673050.pdf
    • https://popuxovalu909409782.files.wordpress.com/2020/07/juxelakovuverugubibi.pdf
    • https://kedisufod.files.wordpress.com/2020/06/47476616895.pdf
    • https://cdn.shopify.com/s/files/1/0434/0776/9750/files/wugonadoweleto.pdf
    • https://cdn.shopify.com/s/files/1/0429/9603/9839/files/91777493918.pdf
    • https://cdn.shopify.com/s/files/1/0433/9925/0072/files/70822978504.pdf
    • https://cdn.shopify.com/s/files/1/0434/4869/6993/files/lituv.pdf
    • https://cdn.shopify.com/s/files/1/0431/6980/8550/files/witubibupuxad.pdf
    • https://cdn.shopify.com/s/files/1/0429/7857/4490/files/sejebida.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_off000055d3.bin
2ee3f8c7cfe336f67d849c52b82ca284d96ae85ff2710d3a47e5ab3ae84c2b58
pdf-font-stream PDF embedded font (sfnt) at offset 0x55D3 5264 bytes
font_01_sfnt_off000067c7.bin
d6e69911b322308f992a006517304f8f55ed63e070a0fc6400aeb4a5b1f7e821
pdf-font-stream PDF embedded font (sfnt) at offset 0x67C7 9364 bytes