Malicious PDF — malware analysis report

Static analysis result for SHA-256 81cf70b507f3ff11…

MALICIOUS

PDF

33.1 KB Created: 2020-08-26 19:11:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: afa61c21fa6ad020b7b4e5fff61b8561 SHA-1: 96e6806ea1b9b6a9c67a74cb801b32a2b3451355 SHA-256: 81cf70b507f3ff11a608bbae1fcdc9513c75f273017a9c81eac2b9c6859ee07f
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to a redirector service known for malicious activity. The document body, though partially corrupted, contains text related to 'exercices physique chimie atomes ions' and includes the malicious URL, suggesting a lure to external content. The ML classifier also strongly indicated maliciousness.

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=exercices+physique+chimie+atomes+ions
    • http://files.meganmilleryoga.com/uploads/1/3/0/8/130874329/4dc825d3.pdf
    • http://files.flintmetroleaguesports.com/uploads/1/3/0/8/130813357/8334412.pdf
    • http://files.melaninlaserclinic.com/uploads/1/3/0/8/130873872/b108c787d73.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0440/3894/6981/files/waxewosowivi.pdf
    • https://cdn.shopify.com/s/files/1/0435/0155/1771/files/86983222432.pdf
    • https://cdn.shopify.com/s/files/1/0436/6086/9785/files/fakemo.pdf
    • https://cdn.shopify.com/s/files/1/0433/3250/1656/files/hanuman_bhajan_odia.pdf
    • https://cdn.shopify.com/s/files/1/0434/3850/6146/files/english_b_ib.pdf
    • https://cdn.shopify.com/s/files/1/0432/8918/2376/files/vivienda_bioclimatica.pdf
    • https://cdn.shopify.com/s/files/1/0428/4468/4454/files/discrete_mathematical_structures_6th_edition_kolman.pdf
    • https://cdn.shopify.com/s/files/1/0431/2681/6932/files/vapevuzip.pdf
    • https://cdn.shopify.com/s/files/1/0428/9875/1641/files/boojum_burrito_bowl_nutrition_information.pdf
    • https://cdn.shopify.com/s/files/1/0427/5427/7532/files/ano_ang_katangian_ng_wika.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/minirefotapobizezuloxot.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/84005007378.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_off000043f7.bin
798bdb2624df676734128a00de8968148583db610ad51f9242adfb46aa6494a6
pdf-font-stream PDF embedded font (sfnt) at offset 0x43F7 5396 bytes
font_01_sfnt_off0000563a.bin
eca06ac3dd1d9b9a424472e309af19cf23a81cebe81f9a91c13d4f75d5719646
pdf-font-stream PDF embedded font (sfnt) at offset 0x563A 9824 bytes