Malicious PDF — malware analysis report

Static analysis result for SHA-256 115a49e9d4c492e2…

MALICIOUS

PDF

117.2 KB Created: 2021-07-13 17:06:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f279fd961dc7575aa986bf39e4568966 SHA-1: 6a024bdc33f81f713867ba05c9fbd7b25e4cdf5b SHA-256: 115a49e9d4c492e2d24b47446557a54c3deb22fddb2ef4b827b639d6272a3db0
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress installations. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The document body is heavily obfuscated and does not provide direct clues, but the heuristic firings and numerous unknown URLs suggest a malicious redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9880

Heuristics 6

  • 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 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://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160857889a218b---xewimisogegigebu.pdf
    • http://salsainkonstanz.de/media/files/92480589947.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/a858d374e09b05c24b1eae9b7a98475d/serelatamavopozoz.pdf
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16098439cd05f1---9801491088.pdf
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/160a9fd1718509---99923204657.pdf
    • http://zrdb-drogbud.pl/Upload/file/rudinixu.pdf
    • http://pinturasoltra.com/images/slider/files/katiwerisaj.pdf
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/0578cafc336c6bb9d0c99348a4384ab3/bidenuxideragu.pdf
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/28475977491.pdf
    • http://osheamaloneynylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wisikegukosadataxolajuxo.pdf
    • http://ecohort.com/userfiles/files/99915350802.pdf
    • http://homenet-spb.ru/userfiles/file/bofazejozosawututukuvopa.pdf
    • http://humanitool.ru/userfiles/file/zotoranurorigafumiga.pdf
    • http://angelcabrera.com/FCKfiles/file/juzewotuw.pdf
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c2b25e14d18---18753364893.pdf
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608fab3183f1f---54039860643.pdf
    • https://bdcomunicazione.it/file/ruwivawat.pdf
    • http://orgue-chantepie.info/FCKeditor/upload/file/47451325768.pdf
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/dm8jguqh9tfocq74d6eno81edu/82762062428.pdf
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b74ec191ba8---tobewibigonegon.pdf
    • http://sgyscom.com/upload_fck/file/2021-6-25/20210625193433934786.pdf
    • http://bularz-auto.pl/images/userfiles/file/zalaboviweralomiborimu.pdf
    • https://actioncoach.com.my/wp-content/plugins/formcraft/file-upload/server/content/files/160897a0a64170---zujidel.pdf
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/8f07be64fbea994f61ba332c3808a6ee/posorifofetunesoku.pdf
    • http://adabaskimerkezi.com/upload/file/gatavekomavejeke.pdf
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/0c4dcd92b94680b3941270747004ffb1/3200669694.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=starship+troopers+1959
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001646c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1646C 16792 bytes
font_01_sfnt_off00017c7e.bin
2091e1e7169989f9d7fbe0d60724fa28f9b2576dd8dad466fa33d14bff7c2b15
pdf-font-stream PDF embedded font (sfnt) at offset 0x17C7E 19448 bytes
font_02_sfnt_off0001ada5.bin
b59b8685499527fe4d3e0787f697ea0e78eea566a480227278acf187e9c0d6f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1ADA5 10628 bytes