Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5831636612c5bb7…

MALICIOUS

PDF

83.4 KB Created: 2021-09-19 03:31:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 3254c667c36157beab95111afa967a13 SHA-1: 7c8e7ef05007ad5b78c213a0b922849ccc63a498 SHA-256: b5831636612c5bb7bafcc66d8d4c96a9ebbbb8127b3866580c1ff71fc5b01d53
200 Risk Score

Malware Insights

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

This PDF contains embedded JavaScript and numerous external URIs pointing to compromised websites, indicating a phishing or malware distribution attempt. The presence of a "link farm" heuristic and the ClamAV detection strongly suggest malicious intent, likely to exploit users via social engineering lures such as urgency or callback requests. The embedded JavaScript is likely used to facilitate the download or redirection to a malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 10

  • 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 link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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
  • 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://nomylo.ru/uplcv?utm_term=setting+up+ntlworld+email+on+android PDF link annotation
    • http://gysanya.com/upload/file/210907203014948655zcsuonhlboul.pdfIn PDF document text
    • https://hiroyoung.com/data/files/88180342714.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1613914a790198---palimilapodiribepuxup.pdfIn PDF document text
    • http://aeklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/76152699491.pdfIn PDF document text
    • http://hotdeals24x7.com/ci/userfiles/files/89975055465.pdfIn PDF document text
    • http://saeronbio.com/userData/board/file/64373919074.pdfIn PDF document text
    • http://ageofwonders.buka.ru/sadm_files/fiwifejejamiw.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/48uich425i1mvg73f9epsg0dkb/80504760127.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16140a263a9879---diganenimu.pdfIn PDF document text
    • https://shreenathtechnologies.com/userfiles/file/60571060716.pdfIn PDF document text
    • https://fidelishospice.com/ckfinder/userfiles/files/87628264241.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/039f01076f55a87a947838b9ba19b149/kudufapusaxuxexejeva.pdfIn PDF document text
    • http://rdmsrl.it/userfiles/files/memitediradelonanaxo.pdfIn PDF document text
    • http://jindi2010.com/uploadfile/files/bogajewesujututibudixu.pdfIn PDF document text
    • http://www.waetsukai.jp/system/ckfinder/userfiles/files/tuvagefimuf.pdfIn PDF document text
    • http://nwatchonline.info/userfiles/file/zudasodonolosire.pdfIn PDF document text
    • http://meruzhankhachatryan.com/app/webroot/files/file/67170602393.pdfIn PDF document text
    • http://kondicionery-vidnoe.ru/upload_picture/file/80667682398.pdfIn PDF document text
    • https://semangkamerah.com/contents/files/posujalusaviposu.pdfIn PDF document text
    • http://cetis156.neutronds.com/assets/js/ckfinder/userfiles/files/68990536723.pdfIn PDF document text
    • http://www.taxivanclass.com/uploads/ckfinder/files/89090707956.pdfIn PDF document text
    • https://tybistanbul.org/resimler/files/dodebo.pdfIn PDF document text
    • https://foodexgida.com/uploads/files/68438575046.pdfIn PDF document text
    • https://mldom.xyz/web/img/podborky/files/tenosanavimibob.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE19 18984 bytes
SHA-256: b16bea30242f1672c74b5a3382d2488471e11e980038d1954aaac344d873f7f9
font_01_sfnt_off00010ed6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10ED6 10828 bytes
SHA-256: d7c66a80281c2ede31a7ebb53090facb284bb3fb266eb37289ed21ef9fa469f9
font_02_sfnt_off000127a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1