Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cf144b95fed763d…

MALICIOUS

PDF

85.5 KB Created: 2021-08-30 01:11:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 371f4d14a3b3a942c7773727912a8154 SHA-1: 45eebc352c38e2cf26100bde39a80c5cbc01ce26 SHA-256: 3cf144b95fed763d18d43d85374f633de90669c5c02ef689b208853398516bf2
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs pointing to compromised WordPress sites and disposable hosting domains, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest this PDF is malicious, likely serving as a lure for phishing attacks or to distribute further malware. The presence of multiple external URIs and link farm characteristics points towards a tactic of initial access via social engineering.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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=my+heart+leaps+up+pdf PDF link annotation
    • http://smithmaloney.com/clients/3/32/32eae1a42220421eddab78da2f55685d/File/58831366662.pdfIn PDF document text
    • http://tele-klass.ru/i/upload/files/rimufuj.pdfIn PDF document text
    • http://www.farnostbobrova.cz/ckfinder/files/puzuvizufez.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/pqf3k4l9iedbm7686uhhgqqq66/jefolujapejevotupevene.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/276dc15988eaa11c11417415f4359950/jexig.pdfIn PDF document text
    • http://connect-senior.ch/uploades/userfiles/file/86258676924.pdfIn PDF document text
    • https://tutorbolivia.com/userfiles/file/lasaragedavujawutatemojo.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a6b2b11cc98---29758938839.pdfIn PDF document text
    • http://badaranquehablar.com/userfiles/files/4167321686.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c6f5110baf---1066178572.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/75qlha3akg50pcnth83dh0vue1/75446022087.pdfIn PDF document text
    • https://kovosluzba-praha.cz/res/file/gomopej.pdfIn PDF document text
    • http://somkuthyoptika.hu/editor_up/75311854444.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606e671363977---vipuzadejemu.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/f169fec8eba6e41530f4b2f7852b52d1/tagogonid.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160fbb8ff29396---labudodup.pdfIn PDF document text
    • http://iphysiology.ru/upload/pomumub.pdfIn PDF document text
    • http://soles2walk.cz/data/file/80740474377.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/er80ghmupa6rq7gqruq44cluv0/5929856214.pdfIn PDF document text
    • http://dailymaytrogiang.com/userfiles/files/dinebutepuguwasepagebap.pdfIn PDF document text
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/b835f9f1e2cc6e59855eebeb0a5a5048/jisuvukilel.pdfIn PDF document text
    • https://arerp.kr/data/file///gapikuramidoliwebawiki.pdfIn PDF document text
    • http://wabasnb.com/files/fckeditor/file/125416768160bf07f31c20d.pdfIn PDF document text
    • http://riversedgefm.com/files/file/85695972813.pdfIn PDF document text
    • http://www.aadhar-interior.com/userfiles/file/sunuvetes.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_off0000e8ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8EC 17776 bytes
SHA-256: eb6120c1ef4c9f32b9e97bc4273b74e47e7e6dbc36d6997d9f07d9fd7a036d78
font_01_sfnt_off00011707.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11707 10484 bytes
SHA-256: 95137b8317aaf50c39f28610ae4f238a99571ce04631b1f06de613a19fac6f56
font_02_sfnt_off00012f0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F0A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1