Malicious PDF — malware analysis report

Static analysis result for SHA-256 77fdd99383581358…

MALICIOUS

PDF

47.6 KB Created: 2020-09-04 00:49:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cabd1cb4898aaf8152d02d344fbcde42 SHA-1: 1f3883c72c99084d4e35192c37b63a22984c14b4 SHA-256: 77fdd993835813581e7a05f13f47f2cb390c518efde82de0873776a0dc632249
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains embedded links that redirect to malicious infrastructure, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body, though heavily obfuscated, contains a URL that appears to be a lure for downloading Windows 10 ISOs. The ML classifier also strongly flagged this PDF as malicious. The presence of numerous external links suggests a link farm or SEO poisoning attempt to drive traffic to malicious sites.

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/wix?keyword=windows+10++iso+32+bit+myegy
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0435/6649/7960/files/35426931598.pdf
    • https://cdn.shopify.com/s/files/1/0433/0491/1006/files/fizokuvixuviw.pdf
    • https://cdn.shopify.com/s/files/1/0432/0067/6003/files/biostatistics_in_pharmacy.pdf
    • https://cdn.shopify.com/s/files/1/0435/8602/7677/files/31960735404.pdf
    • https://cdn.shopify.com/s/files/1/0435/2675/0357/files/26100891099.pdf
    • https://static.usrfiles.com/ugd/71fd01_dde8b0afdd7e4521978d6f0398c55b09.pdf
    • https://static.usrfiles.com/ugd/ef7b09_5b4429211a5847f99849a720c217d169.pdf
    • https://static.usrfiles.com/ugd/53cfc7_0afb8fdcc72e40eaba440ebc6f5c8a52.pdf
    • https://static.usrfiles.com/ugd/7c30af_0585d09c56b04f8081e132473594b7fb.pdf
    • https://static.usrfiles.com/ugd/5f4192_a6d3dca726d948bb83eff9ea1d385c52.pdf
    • https://cdn.shopify.com/s/files/1/0438/0862/0701/files/sim_card_cutting_template.pdf
    • https://cdn.shopify.com/s/files/1/0432/2882/3719/files/partners_in_crime_movie.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007bbf.bin
869760243cb5948267bfce678f10cff0978b7ac7ea7c7f6be22a961923619258
pdf-font-stream PDF embedded font (sfnt) at offset 0x7BBF 5644 bytes
font_01_sfnt_off00008f0c.bin
b2c4e593f016303bd849f58b155594d65618e43a1d079f972e5b34ce6baad402
pdf-font-stream PDF embedded font (sfnt) at offset 0x8F0C 10404 bytes