Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf35f408cae91daf…

MALICIOUS

PDF

81.0 KB Created: 2021-03-08 14:42:51 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 52d6b603c6825da40e0f11fd614be3c6 SHA-1: f701d56f46b2d69b12a3bed9cbe0e97bc08a96bc SHA-256: cf35f408cae91dafae103b37c39a88cbcf08b1195359a8c568d2a543fbfc9574
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains embedded links to known malicious redirectors and is hosted on disposable infrastructure, indicating a phishing or scam lure. ML classification and ClamAV detection strongly suggest malicious intent. The document body, though heavily obfuscated, appears to contain keywords related to the embedded URLs, further supporting the phishing pretext.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://yafferge.ru/wix?keyword=triangle+inequality+mcq+worksheet+answers In PDF document text
    • https://cdn.sqhk.co/wazafanez/gdhhTw8/iphone_x_mobile_ringtone_download_mp3.pdfIn PDF document text
    • http://igcopyrightclient.com/autodesk_inventor_view_2020_freejgt4u.pdfIn PDF document text
    • http://sarhello.online/funny_things_to_put_in_a_class_president_speech5a0ho.pdfIn PDF document text
    • https://fowowudajij.weebly.com/uploads/1/3/5/3/135312379/waladimixe.pdfIn PDF document text
    • http://retapadu.medianewsonline.com/xubejonovezewa.pdfIn PDF document text
    • https://cdn.sqhk.co/gusisitixinu/azjc0jf/absorption_definition_biology_gcse.pdfIn PDF document text
    • http://xafesuvorolivig.scienceontheweb.net/12118038278.pdfIn PDF document text
    • http://theraisins.pro/piweparacnvoo.pdfIn PDF document text
    • https://libepuve.weebly.com/uploads/1/3/1/4/131407284/nobopalodapog.pdfIn PDF document text
    • https://cdn.sqhk.co/wemopizajazo/heRfjbP/6316506063.pdfIn PDF document text
    • http://barajofa.mywebcommunity.org/ncert_maths_book_class_9_solutions_chapter_4_exercise_4.4.pdfIn PDF document text
    • https://cdn.sqhk.co/dodalowogiv/ghfhjz8/44556510316.pdfIn PDF document text
    • http://kesuvajeb.scienceontheweb.net/how_to_replace_delta_shower_cartridge_rp19804.pdfIn PDF document text
    • http://aires.fun/59021179949ewhzo.pdfIn PDF document text
    • http://ericksandoval.com/ralesedomubavawuguno72ol3.pdfIn PDF document text
    • https://pazarufawituxib.weebly.com/uploads/1/3/4/0/134000032/sifigogodejo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://4be8a7ba-6c9a-47a4-99fc-a5961b41a404.filesusr.com/ugd/132250_938f46a3556941d78e94f90926c3115f.pdf?index=trueIn PDF document text
    • https://c7972686-9310-4d97-8ac3-15e828887225.filesusr.com/ugd/8a419d_63d43757fc5a496ca8c9684de3ae4b8c.pdf?index=trueIn PDF document text
    • http://jorasixu.myartsonline.com/presonus_studiolive_32.4.2ai_manual.pdfIn PDF document text
    • https://08c3cc13-1ce0-4add-927e-a3aed263473e.filesusr.com/ugd/ccf397_ac48301bb26f495aa332995c16eaaaee.pdf?index=trueIn 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
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eeb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEB6 6744 bytes
SHA-256: 048fb1891f432488516cd811e7b04d68e7d39e548ca3495625137f8fb0c23ff4
font_01_sfnt_off0000ff9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF9B 5548 bytes
SHA-256: 1e27c7b1683364d4087a3de0ea6e054e19d798c70d57c55d12ef9c748c6faed9
font_02_sfnt_off00011269.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11269 10604 bytes
SHA-256: a3d8e6eb704210cee143b212dd648b27a761b4ac57e73d63dc65ad3e356337dd