Malicious PDF — malware analysis report

Static analysis result for SHA-256 4461aed0cba314b8…

MALICIOUS

PDF

39.0 KB Created: 2020-08-31 16:44:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d23f408061e7ce041e4698fc130bb272 SHA-1: 9eb91530cd0f0f63418ce7ff204601432dee423b SHA-256: 4461aed0cba314b842523ede2491fdfde84abea7a054e4581cd7aa733608ddc1
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.001 Malicious Link

The PDF contains a link farm and a direct link to a known malicious redirector infrastructure, disguised as a Cisco Smartsheet login. The ML classifier also strongly indicated maliciousness. The primary malicious IOC is the redirector URL, which likely leads to a further stage of the attack.

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/wix?keyword=cisco+smartsheet+login
    • https://static.usrfiles.com/ugd/4b7290_08d9423892f440108974d0a090027b5d.pdf
    • https://static.usrfiles.com/ugd/111c46_37fe4323cb464d7ca1c413c3f7e200da.pdf
    • https://static.usrfiles.com/ugd/88a84f_b0278c48a6154bcbb72725fa6b3d16de.pdf
    • https://cdn.shopify.com/s/files/1/0429/6540/1753/files/11983105156.pdf
    • https://cdn.shopify.com/s/files/1/0431/9592/4640/files/85845017639.pdf
    • https://cdn.shopify.com/s/files/1/0429/3538/6265/files/womamafolegepaj.pdf
    • https://cdn.shopify.com/s/files/1/0439/7400/0798/files/79233767396.pdf
    • https://cdn.shopify.com/s/files/1/0435/4542/8122/files/a_letter_love_symbol_images.pdf
    • https://cdn.shopify.com/s/files/1/0430/4997/5961/files/zifupibopelowivilijomot.pdf
    • https://cdn.shopify.com/s/files/1/0437/8768/1952/files/fukefigajemu.pdf
    • https://cdn.shopify.com/s/files/1/0434/5295/6838/files/popazuwevatototojar.pdf
    • https://cdn.shopify.com/s/files/1/0431/6043/6896/files/64358666030.pdf
    • https://cdn.shopify.com/s/files/1/0461/9114/9214/files/ravudekatebipidelutuze.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_off00005b1f.bin
4c14711a2965d264052ec392d9e9ed98b24b318a713ba28a16830347e2748e63
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B1F 5116 bytes
font_01_sfnt_off00006c59.bin
8b44b8a86eefe462486e573f9a0da53348582d03145fa3d25634621fee301e77
pdf-font-stream PDF embedded font (sfnt) at offset 0x6C59 10324 bytes