Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b70270bd3c35ffc…

MALICIOUS

PDF

80.0 KB Created: 2021-05-25 06:29:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 6e43024a1349433b8bb7b98cd52ac7ba SHA-1: 10ef5a4e0e563b7a9e86e055b3caf2fc3b9ddc9f SHA-256: 4b70270bd3c35ffc8b4918c890bb15e3ce20d718f9995a57f13dd44926b86ce2
262 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains a critical heuristic indicating it links to known malicious redirector infrastructure and a large number of external PDF links, suggesting a link farm. The presence of a 'download button' heuristic and a 'password-protected archive lure' heuristic further supports a phishing or malware distribution attempt. The ML classifier strongly flagged this PDF as malicious, and ClamAV detected it as 'Pdf.Phishing.Trojan'. The embedded URLs likely lead to the download of a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 7

  • 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 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.
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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/strik?utm_term=sgh-i337+stock+firmware+download In PDF document text
    • https://zujakeme.weebly.com/uploads/1/3/4/0/134041616/445a6fac2b6.pdfIn PDF document text
    • https://noginoludaven.weebly.com/uploads/1/3/4/3/134374582/ddefc.pdfIn PDF document text
    • https://tofikopu.weebly.com/uploads/1/3/1/3/131381225/defelamulixabe.pdfIn PDF document text
    • https://bigufoxorifef.weebly.com/uploads/1/3/1/8/131871864/sorukik.pdfIn PDF document text
    • https://welaxulisura.weebly.com/uploads/1/3/4/0/134042468/pefeliruxexu.pdfIn PDF document text
    • https://podozipejubepa.weebly.com/uploads/1/3/4/8/134893890/sizoxafepilesa.pdfIn PDF document text
    • https://gimezoribetigaw.weebly.com/uploads/1/3/4/6/134676461/7083867.pdfIn PDF document text
    • https://kozegefiseram.weebly.com/uploads/1/3/1/3/131379202/xevoduzonelakera.pdfIn PDF document text
    • https://xisulufi.weebly.com/uploads/1/3/4/8/134870666/xalatalan-lumatos.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/semuxemakaw/biochips_free.pdfIn PDF document text
    • https://s3.amazonaws.com/fazujo/metformin_starting_dose_pcos.pdfIn PDF document text
    • https://s3.amazonaws.com/vavabi/fletching_guide_rs3_p2p.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0c08204d-e4d2-4dce-af74-5cd351ef2b19/galumolit.pdfIn PDF document text
    • https://s3.amazonaws.com/jusagi/20033757835.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/55c41df3-4af6-4d7e-9cc4-15ad6bbc1bf8/fender_super_champ_x2_review_harmony_central.pdfIn PDF document text
    • https://s3.amazonaws.com/temujonuwu/nofasidolim.pdfIn PDF document text
    • https://s3.amazonaws.com/masevewi/tefirisemulimunusumadeku.pdfIn PDF document text
    • https://s3.amazonaws.com/dowesitobuga/66987640631.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6bcc1722-2f4e-4156-9252-85be58cd917e/delaviers_core_training_anatomy_free_download.pdfIn PDF document text
    • https://s3.amazonaws.com/babetafaperaxov/vakiwenunidoxonuso.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7c219b8a-1910-4e6f-9bde-52c42e6a5caf/20017496121.pdfIn PDF document text
    • https://s3.amazonaws.com/muvazi/san_diego_county_bmp_design_manual.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_off0000f7aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7AA 5968 bytes
SHA-256: 9f2d8fb85b25e18836b25770ab37fd548b0b5305cc8741f75ee7ea905a893956
font_01_sfnt_off00010bf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BF6 11320 bytes
SHA-256: 7fb7429b1b5727497efdb21a223ab199dd07d183d07445a6690e2e1fa8d30234