Malicious PDF — malware analysis report

Static analysis result for SHA-256 874ec439fa81f9d3…

MALICIOUS

PDF

37.8 KB Created: 2020-08-25 08:05:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1d59c7ce3c0446969c42be93ee1890e0 SHA-1: 08016bd0d9f83893ece973fa5cbea66e328dd720 SHA-256: 874ec439fa81f9d3568cfd6b85479824a1f9010c592c166bead8a00a195aa037
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, including a critical link to a known malicious redirector at 'ttraff.ru'. The document body, though heavily obfuscated, contains text suggesting it is a PDF about song chords, which is likely a lure. The presence of a link farm and the ML classifier's high confidence score indicate a malicious intent to redirect users to harmful content.

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=this+is+amazing+grace+chords+pdf+b
    • http://files.vertecreative.com/uploads/1/3/0/9/130969472/tapogid.pdf
    • http://files.edcentricteaching.com/uploads/1/3/1/4/131453021/doletafapu-taxowutoboge.pdf
    • https://cdn.shopify.com/s/files/1/0432/9819/3573/files/66411788536.pdf
    • https://cdn.shopify.com/s/files/1/0430/6308/3162/files/95797269687.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/bugasodaliza.pdf
    • https://cdn.shopify.com/s/files/1/0438/2146/5757/files/pofil.pdf
    • https://cdn.shopify.com/s/files/1/0431/2439/2087/files/gubudezidufevozerob.pdf
    • https://cdn.shopify.com/s/files/1/0431/5850/3573/files/33247569506.pdf
    • https://cdn.shopify.com/s/files/1/0427/5198/3783/files/medanipuvixufebixewo.pdf
    • https://cdn.shopify.com/s/files/1/0436/8308/6489/files/micromax_mobile_brand_fusion_ringtone.pdf
    • https://cdn.shopify.com/s/files/1/0439/3612/0990/files/68926306032.pdf
    • https://cdn.shopify.com/s/files/1/0429/1962/4870/files/vezan.pdf
    • https://cdn.shopify.com/s/files/1/0432/2639/8888/files/77795786632.pdf
    • https://cdn.shopify.com/s/files/1/0430/8484/1124/files/ropevivujuduvod.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_off00004ddf.bin
b8c9a524c3d6caa3261a67ff0b7cd40f04c505dd29496f6aa0a8f7a1aec6de59
pdf-font-stream PDF embedded font (sfnt) at offset 0x4DDF 5676 bytes
font_01_sfnt_off000060fd.bin
788d261dd685aabb8955d0bc55f9fad2614190f5401ba89c950f45f75eb3ac65
pdf-font-stream PDF embedded font (sfnt) at offset 0x60FD 13172 bytes