Malicious PDF — malware analysis report

Static analysis result for SHA-256 53d683f1134e94f1…

MALICIOUS

PDF

91.8 KB Created: 2021-07-06 14:45:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f1b016c27e2fea148067e3c8179a9ff5 SHA-1: 65807731979924cf5a48939406b639b84c3c7ff3 SHA-256: 53d683f1134e94f14a50a0851f900cdb96ce8fd0ecad6d445e43a13495243c8c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple compromised WordPress upload directories and other potentially malicious sites. The presence of numerous URLs, many hosted on disposable domains or compromised CMS installations, strongly suggests a phishing or malware distribution campaign. No scripts were extracted, but the PDF structure and embedded URLs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/160c5c07619a22---fibuxosemuju.pdf
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16089890b79e19---xekubomuzajufur.pdf
    • http://easyreturn.store/userfiles/file/31723012894.pdf
    • http://statewideroadservices.com/clients/879378/File/zedaxagano.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/26e9sjla4jvvmnra5efnph6b6s/vedugirebaxonelidaxideber.pdf
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16079e147448eb---84705645443.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160d992be836fb---nosigotivarolezogi.pdf
    • http://momsystem.ru/public/file/kanewewuxuvarulisunavuz.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160861fb9973bd---62924234316.pdf
    • http://diclenakliyat.com/userfiles/file/liwejujutegatejuzaxixe.pdf
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160810e01d37dd---nomodu.pdf
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/3f9lhpb35j0lr6dj4veb4pr1n3/sozetirona.pdf
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4909f04e16---woxevunubuxupijitule.pdf
    • http://pantryscan.com/123cars/imagefck/file/wedosofifiwekelisuni.pdf
    • http://szao-spb.ru/images/news/file/82618850286.pdf
    • http://chapelguild.com/images/usr/kipiseremanajowiwagupakul.pdf
    • http://benardoutlite.com/admin/fckeditor/fckdata/file/3430625124.pdf
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/e18cmoq8itgfmqfbe6jr556770/4638019704.pdf
    • http://osoboebludo.com/ckfinder/userfiles/files/fizejebivoxakoworus.pdf
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/fe590db2ed89c4f38d38a6fcd96c5083/jeweroligewatiruvegi.pdf
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f831484a7a---13771594765.pdf
    • https://aljazeerahpetroleum.ae/userfiles/files/sazidusatasitapew.pdf
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/71e3378aa471a4c6684085a6e778cece/tosogerupogexuzovevare.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=how+much+sentences+should+be+in+a+paragraph
    • 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_off00010062.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10062 16792 bytes
font_01_sfnt_off00011879.bin
0aaf6372be04849bb6b70c511ad43ea72588520199c942e7a6dcae75f3563e6a
pdf-font-stream PDF embedded font (sfnt) at offset 0x11879 11276 bytes
font_02_sfnt_off0001324e.bin
58a3761daa3306b26800f3bdc757adee163d33fee6ba76d5fc683964e87e0f07
pdf-font-stream PDF embedded font (sfnt) at offset 0x1324E 17568 bytes