Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5ac4ae0fd52ddb9…

MALICIOUS

PDF

36.4 KB Created: 2020-08-12 07:50:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fdf75ddfc3c09cbc9704eaca20607f10 SHA-1: b2e60029bd73c5a967ee1dc4adb5faa501dae766 SHA-256: b5ac4ae0fd52ddb9f658bdc02e3e7f78a9f2a9a1ddae4e4b72f5aa9a93aa4f82
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 pointing to 'ttraff.com', which is used in a lure for a 'small pdf pro download'. The document body also contains this URL and numerous other links, many hosted on Shopify, forming a link farm. The ML classifier strongly flagged this PDF as malicious. The primary attack vector appears to be social engineering via a deceptive link within the document.

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.com/pify?keyword=small+pdf+pro+download
    • http://xobavezo.monsteravisual.com/uploads/1/3/1/4/131438142/9124419.pdf
    • http://files.bolderlegal.com/uploads/1/3/1/3/131381519/1a0681d560e.pdf
    • http://files.debwillardgraphics.com/uploads/1/3/0/7/130739986/kalakafelu-fudinuxazu-fopazutos.pdf
    • https://cdn.shopify.com/s/files/1/0428/7827/1641/files/rinajafes.pdf
    • https://cdn.shopify.com/s/files/1/0434/4581/3414/files/17422533678.pdf
    • https://cdn.shopify.com/s/files/1/0434/5302/2369/files/mysql_drop_table.pdf
    • https://cdn.shopify.com/s/files/1/0429/6622/0956/files/zowawugukowexu.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/40545468116.pdf
    • https://cdn.shopify.com/s/files/1/0431/2865/1938/files/3_way_anova_calculator.pdf
    • https://cdn.shopify.com/s/files/1/0443/0757/9036/files/convert_to_word_farsi_online.pdf
    • https://cdn.shopify.com/s/files/1/0431/2875/0234/files/godsmack_the_oracle.pdf
    • https://cdn.shopify.com/s/files/1/0429/6785/9359/files/duxuwanemeka.pdf
    • https://cdn.shopify.com/s/files/1/0432/9517/8902/files/61498420573.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_off00004dfa.bin
c62587f3e6726ebeece288a58029c238059c59290bae63a7d581d776fbb94b35
pdf-font-stream PDF embedded font (sfnt) at offset 0x4DFA 5204 bytes
font_01_sfnt_off00005fa2.bin
26e11859d26d8b86ce0ceddf6e50e75448b35403848a8ea51fa92c05376c9fb9
pdf-font-stream PDF embedded font (sfnt) at offset 0x5FA2 12496 bytes