Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a12658630fae01c…

MALICIOUS

PDF

147.1 KB Created: 2021-09-18 19:15:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: bec585caef8f98658c0f896577c0a7dc SHA-1: 40462f6d332e78d452ae39b18fe9b034f92b92b4 SHA-256: 2a12658630fae01cbc55f8236e17b6f8c6bb7d6cdb5782b74adc89779498bd78
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample is a PDF containing embedded JavaScript and numerous links. Several heuristics indicate that these links point to compromised WordPress uploads and are part of a link farm designed to obscure the final destination. The embedded JavaScript likely facilitates the redirection or exploitation process, leading to the download of further malicious content, as suggested by the ClamAV detection as Pdf.Phishing.Trojan.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.3952

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://medvor.ru/uplcv?utm_term=pelicula+espanol+gratis PDF link annotation
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135a6f08dc7d---wosafetapot.pdfIn PDF document text
    • https://colegiumaniucarei.ro/ckfinder/userfiles/files/vupigenobolexov.pdfIn PDF document text
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/69829215468.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/af8516b1f5a8e2cf2b54f3d32bce2dcb/36627135532.pdfIn PDF document text
    • https://cyberbirddog.com/userfiles/files/kapekemolav.pdfIn PDF document text
    • http://gianenricofabro.com/userfiles/files/wirijedofibawimejowaxoda.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/575f03920525d992fa9aa51b2c952971/fokumakub.pdfIn PDF document text
    • https://angem.fr/userfiles/file/repafijikesonovemolo.pdfIn PDF document text
    • https://childrencareandliteracysociety.org/userfiles/files/sakewegadovivikujakufigoz.pdfIn PDF document text
    • https://lanhcongnghiepthinhphat.com/upload/files/6275967256.pdfIn PDF document text
    • http://divapharma.com/uploaded/file/67367907700.pdfIn PDF document text
    • http://alfadent-volg.ru/images_uploads/files/wuzewof.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1008e2b01---73597413466.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/buwojivekema.pdfIn PDF document text
    • http://eachfun.com/ckfinder/userfiles/site_eachfun_com/files/jevafexiduda.pdfIn PDF document text
    • https://voyageaventurenepal.com/upload/files/witibufulabodijez.pdfIn PDF document text
    • http://aatmicscience.org/asuserfiles/file/vabavadizelajapigiwizuti.pdfIn PDF document text
    • https://thegmsbihta.in/userfiles/file/lemokuzevozefajugepawe.pdfIn PDF document text
    • http://mcrlclient.gilcom.ro/ckfinder/userfiles/files/37407786891.pdfIn PDF document text
    • https://chambredhotes-savoie.com/ckfinder/userfiles/files/samuvodasasigiluk.pdfIn PDF document text
    • http://paroissedementon.fr/upload/files/97104708161.pdfIn PDF document text
    • http://aygroupmuh.com/image/files/bogikuzifazojemavufofujip.pdfIn PDF document text
    • https://mgs-on-track.com/uploads/misc/files/mulozariratuwiletolufuwu.pdfIn 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_off0001f1bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1F1BD 17472 bytes
SHA-256: 1b73fbe46c1539dda3d7ba2d677df4bed02ee441b11ae8f7ada9c0172ad8055e
font_01_sfnt_off00021e27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x21E27 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0002363e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2363E 10652 bytes
SHA-256: 8db66907795390b621c1e496e2f7d6f327750f0242a4a5a8b0c95ccb4c397f88