Malicious PDF — malware analysis report

Static analysis result for SHA-256 3623bcc5836b8a47…

MALICIOUS

PDF

83.9 KB Created: 2021-09-18 16:08:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f5be435bd6e984c3075cf4b2ce7e0f9d SHA-1: 62234640d4e6195260c6c2c4288442b78da14c24 SHA-256: 3623bcc5836b8a47fc5b0b7f06f5f54caf6491b2847a70d458cbc0964e6ca360
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of techniques used to trick users into visiting malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • 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://synerhu.ru/uplcv?utm_term=pally+live+mod+apk+unlimited+coins PDF link annotation
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/957c4abe05cd0fe43ef8c3b617408826/numafoxipodapojunupipilal.pdfIn PDF document text
    • http://hairtransplantmangalore.com/uploaded_files/userfiles/files/24029250258.pdfIn PDF document text
    • http://fuzoku-kyujin.jp/ckfinder/userfiles/files/nevagevixasurasuwuduzup.pdfIn PDF document text
    • http://101-games.ru/images/uploads/files/29305045349.pdfIn PDF document text
    • http://france-ex.com/images/blog/file/voveriguviferepajoxugimo.pdfIn PDF document text
    • http://baaningdoi.com/file_media/file_image/file/37493097112.pdfIn PDF document text
    • http://sea-cruise.ru/ckfinder/userfiles/files/fereke.pdfIn PDF document text
    • https://arnetbilgisayar.com/upload/ckfinder/files/kunalasuturajojapu.pdfIn PDF document text
    • http://vibrobeton.by/pics/files/6334333084.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/77567623996.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/bf401089f4dbd554f576c8d7465964e0/vizosurexuvajejosikixovux.pdfIn PDF document text
    • http://a-daily.jp/app/webroot/contents_img/files/febofaxadekitasu.pdfIn PDF document text
    • http://currycornersugarland.com/admin/images/file/pisurovurujam.pdfIn PDF document text
    • https://episcopiaoradiei.ro/files/zofibepelesome.pdfIn PDF document text
    • https://implant-drill.com/userfiles/file/25388887763.pdfIn PDF document text
    • http://24horasnoar.com.br/ckfinder/userfiles/files/tijumevifigilirokupuvesa.pdfIn PDF document text
    • http://uniroll.pl/user_images/file/5419549767.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/burujizorijibajajelamerim.pdfIn PDF document text
    • https://2winit.com/Files/files/13809491832.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/466862d90b9b57a8bb43c9a5bd137666/tapigulekinezozamod.pdfIn PDF document text
    • http://rejs2013.cycling-recycling.eu/imgturysta/files/52249291268.pdfIn PDF document text
    • http://work4shop.cz/userfiles/file/1621089926.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613745acbae75---bonefaxetoxexikawaleduxaz.pdfIn PDF document text
    • http://gk-eventus.ru/admin/ckfinder/userfiles/files/vixudoziletituvedoparo.pdfIn PDF document text
    • http://dglytbt.com/upfolder/e/files/20210905110013.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_off0000dadd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDADD 10948 bytes
SHA-256: 2fab737c96eedc57b77589a981b2498006e1f383f9d55ba8c069090fe06e4635
font_01_sfnt_off0000f441.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF441 20132 bytes
SHA-256: e7f2864e60f00dea6c4b0edf75c328f379fb4d96beb2733e4351f828d6d513b2
font_02_sfnt_off000129b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1