Malicious PDF — malware analysis report

Static analysis result for SHA-256 84f4f55799fa5218…

MALICIOUS

PDF

43.1 KB Created: 2020-08-03 11:53:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cd20c963c30054a6865c19615e8f3e0d SHA-1: c7d216974ca937d834675d6b17f52a4d250e4e09 SHA-256: 84f4f55799fa521808de45138f81cda134dbfa98b8f22e2ee1130b1ca9911a4c
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded links, with one identified as a malicious redirector. The ML classifier strongly indicated maliciousness. The document body, though obfuscated, contains URLs that are likely part of a link farm designed to attract traffic or distribute malicious content. The presence of embedded URLs and the redirector link suggest an attempt to lure users 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/pify?keyword=silent+letters+esl+pdf
    • http://zigaz.salmansyed.com/uploads/1/3/0/7/130776131/vanodidaz-niwixubanudon.pdf
    • http://files.emilynahrens.com/uploads/1/3/0/7/130740124/2743833.pdf
    • http://files.missabellahousekeeping.com/uploads/1/3/1/4/131438604/zuwevenowaj.pdf
    • http://files.denvermasktaskforce.com/uploads/1/3/1/4/131406826/6878243.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0440/5883/7142/files/over_and_over_again_nelly.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/vibuzos.pdf
    • https://cdn.shopify.com/s/files/1/0431/3006/0955/files/nigufamesituxawus.pdf
    • https://cdn.shopify.com/s/files/1/0432/7545/2569/files/random_forest_feature_selection.pdf
    • https://cdn.shopify.com/s/files/1/0432/1335/7211/files/vulture_city_3_release_date.pdf
    • https://cdn.shopify.com/s/files/1/0434/5511/9513/files/puvikipel.pdf
    • https://cdn.shopify.com/s/files/1/0431/9281/1669/files/nuresagunudufakatoxuguj.pdf
    • https://cdn.shopify.com/s/files/1/0440/2741/2645/files/tijezixavusoribagibawo.pdf
    • https://cdn.shopify.com/s/files/1/0430/7563/3306/files/93413051576.pdf
    • https://cdn.shopify.com/s/files/1/0430/0688/6051/files/povugonenenivovolisen.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_off000061b7.bin
6d1a824dded5e35295c49ce1b0e0752f7e127d21180c47b389067519cd3cad66
pdf-font-stream PDF embedded font (sfnt) at offset 0x61B7 4928 bytes
font_01_sfnt_off00007289.bin
3878c9ebcfc00c6624ed11be02090513631bcda3b1168c6394ad3a416ce444ab
pdf-font-stream PDF embedded font (sfnt) at offset 0x7289 14748 bytes