Malicious PDF — malware analysis report

Static analysis result for SHA-256 43c76fa689cfd571…

MALICIOUS

PDF

77.0 KB Created: 2021-05-03 04:22:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 1cc999299134c34b6e0793ed3a6de339 SHA-1: de513c5403b2db8f9b52d56345255a606c603ab9 SHA-256: 43c76fa689cfd5717b1a1c7c7f87377d7c3001df4dff9ea59193d65064223951
196 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many of which point to a redirector URL (https://druttle.ru/strik?utm_term=how+to+add+a+pdf+on+wix). Heuristics indicate this is likely a link farm or SEO phishing lure, disguised as a guide. The ML classifier and ClamAV detection strongly suggest malicious intent, classifying it as phishing or a trojan. No scripts were extracted, but the PDF structure itself facilitates the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://druttle.ru/strik?utm_term=how+to+add+a+pdf+on+wix PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4413978/normal_60125030266e1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374699/normal_5fe9b426373ad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489245/normal_5fd1470a3d12f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381291/normal_6019a9033179b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387224/normal_60698970ac3ff.pdfIn PDF document text
    • https://voxonororipesap.weebly.com/uploads/1/3/5/3/135383222/5926762.pdfIn PDF document text
    • https://teduzagegoxow.weebly.com/uploads/1/3/4/4/134400331/ropom.pdfIn PDF document text
    • https://guxitubekin.weebly.com/uploads/1/3/4/2/134267073/5ea07.pdfIn PDF document text
    • https://sagagokibifaku.weebly.com/uploads/1/3/4/6/134625973/7051151.pdfIn PDF document text
    • https://maviwodoke.weebly.com/uploads/1/3/1/6/131606431/nujixuz-bonaposalalif-kinoti.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/gapivegek/small_unit_tactics_formations.pdfIn PDF document text
    • https://s3.amazonaws.com/tesodagiwor/wafubaforutosepi.pdfIn PDF document text
    • https://s3.amazonaws.com/fajeloninesitel/hello_kitty_converse_platform.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d4b4873a-533b-4c0b-9ecb-5b77fb554a29/white_t_shirt_dress_new_look.pdfIn PDF document text
    • https://s3.amazonaws.com/satulibaren/theory_of_database_management_system.pdfIn PDF document text
    • https://s3.amazonaws.com/vebisop/kufozekasefixakewap.pdfIn PDF document text
    • https://s3.amazonaws.com/zozuxukoxo/the_republic_for_which_it_stands_epub.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3abda9ae-6301-4a5f-8d9c-5bcb39cfb4b0/kasazunoxogil.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0db5bfed-bde2-4af7-ac51-3da047562ae5/zurusakulovupom.pdfIn PDF document text
    • https://s3.amazonaws.com/jexijer/nunebupabovato.pdfIn PDF document text
    • https://s3.amazonaws.com/xajowu/nora_roberts_the_awakening_book_review.pdfIn PDF document text
    • https://s3.amazonaws.com/redegelesibif/long_island_sound_striper_fishing_report.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7973809d-8c55-410f-ac16-266bd4b47eac/fokibebipusu.pdfIn PDF document text
    • https://s3.amazonaws.com/nuruvapozixix/how_to_find_4_digit_tv_code.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f10a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF10A 4852 bytes
SHA-256: 56a58d8d5a3ed52e03b8caa17d25a923a5b12c34619c30fab4b7794f4b464c7e
font_01_sfnt_off000101b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101B8 10812 bytes
SHA-256: 3511f75e0ae10d9ed125c948a4313f6ec8dd436ac98cd785225557a90c471e3c