Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab23878a2500d119…

MALICIOUS

PDF

41.4 KB Created: 2020-08-21 10:18:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f6b4326a0ebfc6f693a43eb11b23ba59 SHA-1: 7f4391a8593d08736618c595a987314c20fa9d33 SHA-256: ab23878a2500d11921cd34d5bbc02deb6d85fd1a3adb3862c3cbfbcbfb5aa119
152 Risk Score

Malware Insights

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

The PDF contains a prominent link that, when clicked, redirects to a malicious URL. The document body text, though heavily obfuscated, contains the lure 'Autocad lt 2020. 1 update' and the malicious redirector URL. The PDF also hosts a large number of links to other PDFs, likely for SEO poisoning to increase visibility.

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/pify?keyword=autocad+lt+2020.+1+update
    • http://files.melissamakesmoves.com/uploads/1/3/1/4/131437530/bafowuxilan.pdf
    • http://files.personalrenewal.org/uploads/1/3/0/7/130739298/mitawarajuduw.pdf
    • https://cdn.shopify.com/s/files/1/0446/3765/1107/files/go_math_assessment_resource_with_answers_grade_7.pdf
    • https://cdn.shopify.com/s/files/1/0430/6586/8437/files/septa_128_bus_schedule.pdf
    • https://cdn.shopify.com/s/files/1/0430/4191/5042/files/empirical_distribution_function.pdf
    • https://cdn.shopify.com/s/files/1/0431/1570/8577/files/72394476336.pdf
    • https://cdn.shopify.com/s/files/1/0431/7046/3912/files/sigijodi.pdf
    • https://cdn.shopify.com/s/files/1/0430/7740/2778/files/87817647951.pdf
    • https://cdn.shopify.com/s/files/1/0429/0645/2127/files/hollow_knight_failed_champion.pdf
    • https://cdn.shopify.com/s/files/1/0431/7757/4551/files/relusana.pdf
    • https://cdn.shopify.com/s/files/1/0439/1393/7064/files/bendy_ink_machine_song.pdf
    • https://cdn.shopify.com/s/files/1/0428/7227/5103/files/xozateropusimozigo.pdf
    • https://cdn.shopify.com/s/files/1/0429/2080/4518/files/overhead_door_legacy_manual.pdf
    • https://cdn.shopify.com/s/files/1/0432/4209/4756/files/anodyne_adjective_form.pdf
    • https://cdn.shopify.com/s/files/1/0429/7133/2767/files/karazawakuwujolowofo.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_off00006423.bin
f2df3a1f0f41574ef13acf6a91924a54492cceb54994cb66b1eb7bbf2a73ff7c
pdf-font-stream PDF embedded font (sfnt) at offset 0x6423 5140 bytes
font_01_sfnt_off000075b2.bin
afb8e8ed111ac8247b7f7d5038487f96397ec74126f642957edbd6960df2415f
pdf-font-stream PDF embedded font (sfnt) at offset 0x75B2 10256 bytes